Zero Two

Zero Two (ゼロツー) is the main heroine of DARLING in the FRANXX. Zero Two is a human-klaxosaur hybrid and a member of the APE Special Force, making her an elite Pistil. She is currently based in Plantation 13 under priority surveillance. She and Hiro are in a romantic relationship.

Zero Two and Hiro are the newest members of Squad 13. The pair pilot the most powerful FRANXX, the Strelizia.

Appearance
Zero Two has long pink hair and a pair of red horns on her head. Her eyes are cyan with pinkish-red eyeliner. Her eyes turn red without her headband. She has a slender and athletic figure; she is the tallest girl among the squad and about the same height as Hiro.

Zero Two's full ensemble is composed of a white military cap with a matching overcoat and boots. She is at often seen wearing her signature red uniform, black tights, and white boots. She also wear a limiter headband on her horns.

Zero Two's original pilot uniform was a tight, dark red bodysuit with a cap of the same color. After she became an official Plantation 13 Parasite, she, like the other Squad 13 Pistils, started wearing a white uniform, with red accents to represent the FRANXX she pilots.

As side effects of aggressively riding Strelizia, Zero Two fangs and horns can grow at an alarming rate and her eyes shine red when angered, even while wearing her limiter headband. It once got to the point when her face was deathly pale, her eyes blood red and her horns long enough to touch the ceiling. In this stage, she can't be controlled.

When Hiro consoled Zero Two in episode 15, her horns shattered and he brought her to life again. She filed her horns again after that.

In episode 17, Zero Two was given a flower headband by Miku and wore it for the rest of the episode.

As a child Zero Two looked much more like a monster, with red skin, long sharp nails, and fanged teeth. While her eye color was the same, her sclera were red instead of white. Her horns were also much larger in comparison to her head, and her hair was lighter shade of pink. In terms of clothes all she was given was a dark grey cloak, and white wrappings from Hiro that substituted for shoes.

Personality
Zero Two's personality is dangerous and alluring. She's an elite pilot with the pseudonym "Partner Killer" (パートナー殺し), given the mysterious happenings of her co-pilots dying after a short number of FRANXX outings. She appears to be playful towards Hiro and sometimes shows some sense of humor; even so, she follows her duties. It is implied in Episode 7: Shooting Star Moratorium that she knows more about the outside world than the other members of Squad 13.

When questioned by Hiro as to why she wanted to kill Klaxosaurs, Zero Two answered that maybe it was because she was a monster. She seems to show resentment towards those who view her as a monster; eg Ichigo.

Zero Two's behaviour is also quite childish, as she wiped her hands on Zorome's uniform and saw Hiro while he was naked. Zero Two demonstrates impressive agility performing somersaults and flips then landing on her feet everytime as if she was lighter than a feather. During, Episode 8: Boys x Girls, Zero Two tricks the girls into believing she will cooperate with them in their feud with the boys, after which she tricks the boys into walking in on the girls while they were bathing. Then proceeding to steal both the boys and the girls clothes. While being chased by Hiro, she teases him and laughs while running throughout the house.

Zero Two eats with her hands, never seen to be using cutlery. She often licks people, such as herself, though she doesn't like how she tastes; Hiro, who tastes like danger; Ichigo who tastes sweet ; and Ikuno who taste like secret. Zero Two has a sweet tooth. She is almost always seen with her lollipop. She also pours inordinate amounts of honey on her meals.

Zero Two wished to see the ocean and would also like to taste it; her wish is fulfilled in ''Episode 7: Shooting Star Moratorium. '' She finally swims in the ocean and licks herself, satisfied it finally tastes salty. Zero Two is also fascinated by rain.

Around Episode 10: City of Eternity and there on, Zero Two becomes more melancholic and silent. Barely speaking or showing any affection to Hiro, despite her behavior in previous episodes. During episode 11, Zero Two acted reckless while fighting Klaxosaurs, disregarding Ichigo's orders or plans, and getting annoyed that Hiro got in her way.

In Episode 12: The Garden Where It All Began, Zero Two becomes much more aggressive both to Hiro and while battling Klaxosaurs, chasing the klaxosaurs until she is away from the group. Then repeatedly stabbing a klaxosaur corpse she had just killed, maddeningly saying she will kill more klaxosaurs, scaring both Miku and Ichigo.

She has also developed a hatred towards mirrors, as she is seen crushing the hand mirror that Hiro had gifted her in frustration, and proceeded to smash every single mirror throughout the border house, possibly due to them reflecting her more monstrous appearance.

Revealed in Episode 13: The Beast and the Prince, during her time at the Garden. Zero Two acted like a wild animal or a feral child, eating with her hands (which she does even now), growling and making other vocal noises instead of speaking, chasing after some mice that were near her, as well as biting Hiro when he tried to get her to spit out the mouse she had just caught. However, after a gentle stroke from Hiro, she immediately felt sorry for doing so. It was during her time with Hiro that shaped much of her personality and quirks in the present, such as her sweet tooth, and the nickname she has for Hiro "Darling".

In Episode 14, Zero Two feel apologetic towards Hiro after realizing that Hiro is her long lost darling. But, having fed up with Zero Two antics, Ichigo forcefully didn't allow her and Hiro for even a visit. Ichigo even proposed to Nana that unless Zero Two is kicked out from Squad 13, they won't cooperate at the next mission, much to Zero Two’s disbelief and frustration. Although in the end, Goro was finally able to convince Ichigo to let Zero Two visit her Darling, Hiro’s sudden disappearance enraged Zero Two as she feel deceived and proceeded to beat the members of Squad 13, mainly Ichigo. When Hiro reappeared and unintentionally called Zero Two a monster, Zero Two finally broke down, leading to her deportation.

In Episode 15, After Hiro finally meet her again and consoles her. Zero Two personality reverts back to her former, cheerful self.

History
Two years prior to the main story line, Zero Two piloted with Plantation 26. She was reckless and showed no concern for others; causing the death of 090's partner.

Episode 01: Alone and Lonesome
Zero Two is seen on the carrier. She asks Nana where she can find an ocean, as she feels like swimming.

Zero Two is later spotted by Hiro skinny dipping in a lake near The Birdcage. She disappears, prompting Hiro to assume she is drowning and in need of rescue. Zero Two jumps out of the water with a live fish in her mouth. She spits out the fish and licks herself believing that she will taste "salty", to her disappointment.

Zero Two, in the nude, begins to converse with Hiro. She then tackles him into the water and licks his cheek, remarking that he tastes "dangerous" and she loves it. His "taste" coupled with the fact that he was not afraid of her horns prompts her to propose that he become her "Darling". Before Hiro can accept, Nana and Zero Two's partner arrive to retrieve her.

During the welcoming ceremony, a klaxosaur appears and attacks the new FRANXX, damaging the garage. Zero Two piloting Strelizia saves the Parasites, notably Goro and Ichigo, from a would-be particle beam. Strelizia and the klaxosaur battle, causing catastrophic damage to the outer wall of The Plantation. Strelizia is overcome and is flung into a section of The Plantation, crashing where Hiro had been viewing the battle.

The lifeless body of Zero Two's partner, 081, drops out of the derelict Strelizia. Zero Two emerges from the wreckage bloodied and tells Hiro she'll have to pilot the Strelizia alone as "she always has". Hiro begins to reprimand her that if she pilots a FRANXX in her current state she'll die. Zero Two claims she isn't afraid of death and if she doesn't do it countless more people will die from the klaxosaur attack. Hiro declares that he will ride with her. Zero Two asks if he's ready to die which Hiro states he doesn't know but he may very well be if he can't pilot a FRANXX. Zero Two extends her hand to him, mirroring their initial meeting at the lake. Hiro takes her and she pulls him into the cockpit declaring him her "Darling" and they kiss. The kiss reactivates the Strelizia and the Hiro-Zero Two pairing unlocks its "Iron Maiden" form to the amazement of Dr. FRANXX and everyone else.

The new Iron Maiden Strelizia begins to overpower the klaxosaur and destroy its core effectively killing the mechanical beast. In the aftermath, repairs are being done to the damage of the klaxosaur attack, Zero Two carrying an unconscious Hiro alight from the now deactivated Iron Maiden Strelizia. Zero Two gazes into the sunset and shoots Hiro a gleeful smile saying "I found you, my Darling!"

Episode 02: What it Means to Connect
Zero Two is having breakfast at The Birdcage with the Parasites. She completely covers her meal in honey and proceeds to eat it with her bare hands to the disgust of all the Parasites except Hiro. She is approached by Zorome in an attempt to "hit on her" while putting down Hiro. She begins to wipe her honeyed hand on his uniform mortifying Zorome. Zero Two takes the pitcher of honey and starts sitting with Hiro and begins pouring honey all over his breakfast as well. When asked by Hiro as to whether or not he actually was able to activate and pilot Strelizia with her, she reassures him, stating that he was "amazing" and calls him "darling", much to the shock of the other Parasites (and to Ichigo's chagrin in particular).

Nana enters the room and informs them that Zero Two is on "standby" awaiting further orders from HQ. She also commands her to go back to her own table and not to converse with the Parasites. Zero Two antagonizes Nana stating that she merely wanted to have breakfast with her darling.

Later in the hangar, Zero Two is confronted by Ichigo. Ichigo thanks Zero Two for saving their lives but warns her to stay away from Hiro so as not to get his hopes up and hurt him, declaring that she is not part of "their" squad. Zero Two approaches her and asks Ichigo what she "is" to her darling. Ichigo states that she is the leader of the squad. Zero Two begins to sniff her and lick her cheek astonishing Ichigo. Zero Two says she tastes "sweet" and that she likes her taste before gleefully leaving.

During the discussion for Hiro's parasite promotion test, Zero Two volunteers to be his partner, him being her darling. Zero Two's proposal is met with harsh resistance by Ichigo, stating that she is not part of the squad and that if the test is merely to measure Hiro's aptitude it should work with her; having Zero Two participate would be unnecessary. Nana informs Zero Two that HQ hasn't authorized the use of the Strelizia so Hiro will have perform with one of his squadmates. Zero Two concedes, stating that her injuries haven't completely healed yet. She allows Ichigo to have Hiro, telling her to go for it "this one time" and to make sure to take care of "her" darling.

After Ichigo's subsequent failure to properly pilot with Hiro, Zero Two is shown flipping her hair in the wind and triumphantly eating her lollipop while leaving the training grounds.

Episode 03: Fighting Puppet
Zero Two is first shown waiting for Hiro to finish his solo training. After he finishes, he finds her asleep in an atrium. Once she wakes up, she takes him around the facility. However, due to Hiro's status he has limited access to certain areas, whereas Zero Two has an S-Class ID which implies unrestricted access. Thinking quickly, Zero Two takes Hiro's hand and they "waltz" through the doors, tricking the system.

Upon gaining access, Zero Two leads Hiro to the Inner City of Plantation 13. While Hiro is awestruck by the view, Zero Two overlooks the city melancholically. Hiro shoots her a grateful look, and she asks him why he's staring at her. Hiro replies that he's trying to think of a name for her. Zero Two then jumps the rail and begins to walk out onto the ledge. She expresses her depressive view of the city, its inhabitants and life. Zero Two then asks Hiro to run away with her, offering to get him out of the plantation. Before Hiro can answer, Zero Two pretends to fall but actually somersaults back the the safety of the balcony. She lightly jokes that she was kidding.

Zero Two appears next when the underground mission against the Conrad-class klaxosaur went awry. While the team celebrates their apparent victory, Zero Two shows up in a dark corner remarking that it isn't over. All of a sudden a swarm of similar klaxosaurs and a giant version of the initial one begin to ambush the FRANXXs. As the situation grows increasingly dire, Zero Two consistently prods Nana into letting her ride with Hiro in order to save them. Nana persistently denies her, till Hiro submits the Zero Two ride with Mitsuru, the only available "official" stamen, in order to save the squad. Zero Two is greatly disappointed in Hiro, giving him the silent treatment as she begrudgingly embarks partnered with Mitsuru.

The pair then race to rescue the squad. Initially, Mitsuru pilots the Sterlizia on par with Hiro, proposing that Zero Two take him on as her "official partner". Zero Two puts him to the test and goes "All Out", prompting Nana to initiate the retrieval of Strelizia. A bloodied deactivated Strelizia emerges in the aftermath. Zero Two emerges from the robot and gives Hiro a light wave and smile. Mitsuru does not emerge from the FRANXX. He is shown to have passed out in the cockpit, bloodied and broken, on the brink of death.

Episode 04: Flap Flap
In the aftermath of Mitsuru's near-death experience, Zero Two is told to return to the frontlines by Nana on Papa's orders and the Strelizia is grounded, much to Zero Two's dismay.

Zero Two finds Hiro in the boy's bath and asks him to run away with her and leave his "weakling" comrades. Her mood dampens by Hiro's visible fear of her and asks him if he's like everyone else; if he thinks "she's a monster".

A giant centipede-like razor klaxosaur attacks the carrier sent to acquire Zero Two. Plantation 13's Parasites are deployed to combat it, only to be ambushed by another klaxosaur. Zero Two and Hiro change into their suits and rush into the situation room when Nana tells her that it won't change her decision, that the Strelizia is not authorized to "fly".

At this point, armed security personnel arrive to collect Zero Two and return her and the Strelizia to the front lines by any means necessary. Zero Two gives a long goodbye to Hiro remarking about how she "felt like things could work out too" and that she wanted to be with him. In lieu of a kiss, Zero Two pokes his forehead with her horns and departs with the soldiers.

While being escorted by the guards to the carrier, Hiro catches up to her, however unable to reach her due to restriction system. Hiro begins to shout out to her and apologize for his prior hesitation in the bath. Hiro explains that his fear was not of her inhumanity, but a lack of his own resolve. Hiro confesses that he doesn't care about riding the FRANXX and that he just wants to ride with Zero Two, begging her not to go. Zero Two pauses in the face of his confession. She then does a backflip, disarming one guard and using his rifle to crack the glass barrier above Hiro. She performs an aerial flip, breaking through the glass to reach Hiro. Now reunited with a bashful Hiro, she coaxes him to reaffirm his confession, asking him, "You wanna ride me, huh?". Hiro affirms that he does and Zero Two asks him to say it one more time; he then shouts it out for her.

Zero Two takes Hiro in her arms and they assume their waltzed pose in order to pass the security restrictions and break through to the Strelizia. Once in the cockpit, Nana orders them over the comm to get out and that they do not have permission to launch. Zero Two declares she's going out with her darling and cuts Nana off mid-sentence. Hiro pauses, due to his anxiety of failing to pilot a FRANXX yet again. Zero Two reassures him that he can do it, later rephrasing it to "they" can do this. Now revitalized by Zero Two's encouragement, they pair-up and the Strelizia destroys the carrier and takes to the skies, en route to rescue the Parasites once again.

Episode 05: Your Thorn, My Badge
Zero Two first appears waiting for Hiro so that they can have breakfast together. She insists on sitting beside Hiro at Futoshi's expense, thereby forcing Futoshi to sit at the girl's table by Kokoro's invitation. While Ichigo gives the morning prayer, Zero Two is hard at work slathering her entire breakfast (and Hiro's) with honey. She then begins feeding Hiro to the disgust of Goro and the jealousy of Zorome. Futoshi and Kokoro imitate them while Ichigo silently ponders into her teacup.

After breakfast, Hiro gives Zero Two a tour of The Birdcage and their life as parasites. Zero Two then divulges that she'll soon be living there too, her announcement causes displeasure among the Parasites, especially from Ichigo who immediately confronts Nana about this development. Ichigo accepts her stay as the will of Papa then personally sees Zero Two to her accommodations. Zero Two finds Ichigo "bossy" for not letting her share a room with Hiro.

During the joint briefing between Plantations 13 and 26, Hachi informs them that Zero Two and the Strelizia will guard the main pipeline during the kissing. The plan is met with strong opposition by the leader of the Plantation 26 parasites. He recounts an operation from 2 years prior with Zero and his Parasites. He denounces Zero Two as "reckless and shows no concern for others". He even divulges that she is the reason his previous partner is dead. Zero Two utters "Weaklings die, Big Deal". The leader is about to attack Zero Two until Hiro intervenes and defends her honor, thus defusing the situation.

Later that night, Goro spots Ichigo and Zero Two sneaking out at midnight. Apparently Ichigo pulled Zero Two aside to ensure she stay in line for the upcoming mission. Zero Two dismisses her for being bossy again and begins to leave. Ichigo grabs her wrist and begins to beg Zero Two not to push Hiro too hard. Ripping herself from Ichigo's grasp, Zero Two responds that "darling (Hiro) said that he wanted to ride with her". Ichigo continues to beg her not to put a heavy burden on Hiro. Zero Two questions Ichigo if she wants Hiro and reminds her that she tried to ride with him and that "they" didn't work. Ichigo exclaimed to leave her out of it; Zero Two tells her that she should stay out of it. Ichigo asks if she's trying to "suck him dry", Zero Two declares "darling belongs to me". An agitated Ichigo warns her that Hiro could die. Zero Two brushes it off saying that he could, and if he did then he wouldn't have amounted to much. Angered and frustrated, Ichigo calls her heartless and inhuman. She then slaps Zero Two hard so hard that it damages her headband, knocking it off. Zero Two becomes enraged, her eyes and horns start to glow a malevolent red. The red-eyed Zero Two, glaring at Ichigo, questions her on what it means to be "human". Frightened by the being before her, Ichigo runs back to the birdcage in tears and it starts to rain. Zero Two is calmed by the feeling of the rainfall.

The next morning, Hiro goes outside and approaches a soaked Zero Two by the lake. It is implied she spent the rest of the night out in the rain. Zero Two tells him that everything smells nice after it rains. Zero Two reminisces of the time they first met. Hiro thanks her, stating that the reason he's still there is because of her and that she gave him the chance to pilot a FRANXX. Zero Two unzips his uniform revealing a blue tumor. Zero Two asks him if it hurts and if he wants to walk away from being her partner. Hiro admits that it hurts, but confirms that he'll ride with her. Zero Two smiles and begins to joyfully laugh and dance, having found someone willing to give his life for her.

Episode 06: DARLING in the FRANXX
On the dawn of the mission, Hiro spots Zero Two exiting the armoury. She glances back at him but doesn't approach as Ichigo is present. Hiro quickly ends his conversation with Ichigo and meets up with Zero Two.

During defence of the kissing, Zero Two and Hiro and oversee the battle while guarding the main pipeline, much to her boredom. Zero Two remarks that the Plantation 13 parasites'  tactics are all over the place and that they're barely hanging in there, as they are being overwhelmed by just 4 Conrad-class klaxosaurs, in contrast to the other squad's calculated and efficient method of combat. Hiro asks Zero Two why she fights klaxosaurs; she replies that the reason is because she's a monster too. Zero Two shoots the question back at an unsure Hiro, who shrugs and states it's to protect Papa and all the adults in the plantations. Zero Two remarks his answer is lame. Hiro proposes that if the squad needs their help they should move out, to which Zero Two agrees.

Without further ado, Zero Two and Hiro charge into battle and begins killing the klaxosaurs in bundles. Once the minor klaxosaurs have been wiped out due the collective efforts of both squads (and mostly the Strelizia), Target Beta, initially a massive cube-klaxosaur with horns transforms into a humanoid form and begins its advance to the pipeline. Hiro's health deteriorates as a result of clearing the minor klaxosaurs, Zero Two checks in on him reminding him that Target Beta is real threat. Once the parasites pin down Target Beta, the Strelizia flies into the air. Hiro aims to finish it in one-blow with a downward thrust as his final act. The attack was seemingly successful as Target Beta collapses. However, Target Beta punches the Strelizia off and quickly reassembles itself once again, this time into a battering ram preparing to attack the Strelizia. The Strelizia deactivates, showing Hiro has died at the cost of that last strike.

The Strelizia takes the full brunt of Target Beta's attack, sending it crashing into the main pipeline. With the link between Zero Two and Hiro now disconnected, Strelizia enters Stampede form, much to the horror of his squadmates. Zero Two attempts to retaliate, however futile, as she is embedded in the pipeline as Target Beta continually rams into it. Zero Two devolves into a primal state as she desperately tries to defend against the unending attack. Hiro miraculously revives, and the traces of the tumor rapidly disappear. Hiro calms a distressed Zero Two with an embrace, declaring he's her partner and he won't leave her alone. The Strelizia returns to it's Iron Maiden Form and knocks down Target Beta, rekindling the hope and amazement of everyone (especially Dr. FRANXX). Squad 13 repeats the earlier maneuver but with an upward strike. The attack shoots Target Beta into the sky as wings of light appear and impale it, finally putting an end to the gargantuan.

In the aftermath, Hiro is the one carrying a fatigued Zero Two out of the Strelizia this time. He is greeted and hugged by his comrades amazed that he is alive, breaking the "3 Ride" record of Zero Two. Standing apart from the celebration, Zero Two watches them. She turns to the Strelizia contemplating that she has to kill more and more klaxosaurs.

Episode 07: Shooting Star Moratorium
Zero Two tells Dr. FRANXX that they didn't have to come all the way. Nana introduces Hiro to Dr. FRANXX, the creator of FRANXX. She begins to introduce a boy, but he stops her. He approaches Hiro and says that he's the first person to survive Zero Two. He says that he has an interest in them. Hachi tells the doctor that Strelizia and Code 002 are transferred into Plantation 13's purview. He waves at him and says that the geezers already told him. When Hachi announces that they're officially partners, Zero Two hugs Hiro.

Dr. FRANXX tells Hiro not to let him consume his emotions if he wants to always be her partner. Otherwise, he'll suffer.

Later, after the successful kissing with Plantation 26, Unit 13 is given a special vacation. Zero Two, along with a majority of the other children, is excited to be at the ocean. She pulls Hiro to the water. She splashes him and they laugh together.

Hiro follows Zero Two into the water and the three boys begin watching them. She notes how nice it feels to swim in the ocean. Hiro seems embarrassed when he looks at her and she asks what's wrong. He says she looks good, but she can't look her in her eyes. She thanks him for all he did for her.

Zero Two seems to be about to kiss Hiro, but she instead licks his cheek. She teasingly asks what he was expecting. She says that a kiss is a declaration that the other person belongs to you and you should only kiss the person you love. She asks if he maybe kissed someone else. Before he can answer, Goro, Zorome, and Futoshi pull Hiro under the water, leaving her alone in the water.

Mitsuru tells the group that he found something strange and leads the group through a thin pass. Zero Two walks along at the back of the group through the pass and the forest path before being brought to what appears to be a city. Zorome comments that it's nothing like the cities that adults live in. Kokoro asks if people live there, and Mitsuru replies that he'd never heard of anyone living outside the plantations.

Ichigo comes to a bookstore where she sees a poster featuring a kissing couple. She thinks of her and Hiro's kiss and touches her lip. Zero Two suddenly says behind her that she did it with Hiro. Ichigo is startled and asks her what she means. She answers "kiss" and says that she probably isn't ready for it yet. Ichigo says that she has too. Zero Two asks with who and says that it should only be shared with someone special. She asks if that person was special to her. Before she can answer, Goro calls her and he and Hiro wave them over.

They walk back to the rest of the group and Miku says that she's exhausted. Kokoro agrees. Zorome wonders about the city and Ikuno says that they can be sure that it was part of civilization. Goro asks if people lived there in the past. Zero Two answers that they abandoned it and that humans used to live on the surface. She says that there are tons of places like that around the world.

Back at the beach, food had been delivered. They all begin eating and Goro hands Zero Two a shish kabob. She tells Hiro that she's going to go swimming before running off to the sea.

Hiro asks why they think humanity abandoned the surface and wonders if humanity hadn't started extracting magma energy, if the klaxosaurs wouldn't have showed up. Mitsuru asks if he's doubting Papa and the rest. He says that they moved into plantations in order to protect mankind. This pumps Zorome up, to Mitsuru's disdain, and Futoshi as well. Zorome asks if he agrees and when he shyly answers, he asks why he's acting so aloof when he's their teammate. Miku says that they have to put in both his and Naomi's share of the work. Kokoro says that she finds it reassuring that they're with them. Futoshi and Goro agree. Ichigo stands and officially welcomes him and Zero Two to the squad. He thanks them all.

When Zorome finds a crab, Futoshi wants to eat it. Mitsuru is surprised that he still wants to eat, causing the others to laugh. Zero Two watches this from the water.

That night, while everyone but Hiro and Ichigo are asleep, Zero Two watches the shooting stars from a rock.

Episode 08: Boys × Girls
As the parasites are fighting a klaxosaur, it spews goo. It leaks into the cockpits and melts the girls' parasite suits. Though the boys begin spacing out, they don't tell the girls and they finish off the klaxosaur. Hiro finally tells Zero Two and the rest of the girls realize what's happened.

The girls cover themselves with a towel and glare at their partners. Besides Zero Two, who doesn't seem to mind. The boys look embarrassed, and Goro explains they only didn't tell because they didn't want to distract them during the battle. Futoshi says he didn't because he found Kokoro to be amazingly beautiful. Kokoro turns red and looks away. Mitsuru calls him an idiot and walks away.

Zorome tells him that it's not like it hurt them to be seen, and Hiro says that Zero Two said it is better that parasites are a bit pervy, which Zero Two confirms. This annoys the girls further.

As the girls shower, they discuss what happened and wonder how long they had been ogling them. Kokoro says they're taking things a bit too far, but Miku says that should quit.

The girls begin splitting the area of the house between the boys and girls. Zorome begins to cross, but is threatened by Miku and stops. Dr. FRANXX and the two apes watch. Hachi says that it's unprecedented for so many members of a squad to hit puberty at once. Nana says that it has always been at most one or two together. Nana says that if they go by Ape's manual, they should intervene and resolve the issue immediately. Dr. FRANXX asks what would be the point of the test team if they did that. He tells them to observe and write for him detailed reports. He tells them not to interfere or tell "the geezers."

The girls talk about what's happened but notice that Zero Two is ignoring their split. As they go to reprimand her, the boys walk in from swimming in the lake wearing only boxers. Though Miku tells them to get dressed, he says they can do whatever they like on their side. As they clean the bath, Ichigo says that it must have been Goro's idea.

When they go to eat, the boys are already there. Goro says that they've already taken over the area. Miku becomes annoyed, so Goro suggests that drop all the rules and eat together. Zero Two walks in and Miku attempts to follow her, but the other girls pull her back.

In the yard, Zero Two plays with a ball as Hiro says that everyone's gotten too stubborn and they need to do something. She says she thinks the opposite and that they need to spice it up a bit.

When Kokoro enters a small greenhouse, she finds Mitsuru. He slips his medication into his pocket and she asks if he has an interest in plants as he tucks a baby book into her pocket. He says no, and that it's a good place for being alone. Kokoro says she begged Nana to let her take care of the greenhouse. She tells him about the meaning of some of the flowers and then asks if he doesn't mind chatting with her when the girls and boys are "feuding." He says it's stupid and can't be bothered. Kokoro is amazed and says it takes a lot of courage to refuse to toe the line and she was too scared to say anything. When he walks closer to her, she panics and drops her book. He says that it doesn't matter to him and walks out.

Miku, Ichigo, and Ikuno look for food and go to the first floor. They had never been there before, and find a room that says "keep out." Ichigo wonders how long things will go on like that and Ikuno says she wouldn't mind if it didn't ever. Zero Two licks her and says she tastes a secret. She begins to walk away, but Miku tells her to wait.

In one of the girls bedrooms, Miku asks whose side she's on. She says that they're just playing around, but Ichigo says they're serious. Hearing that, she says she'll play along.

She changes the girls only bath sign to allow boys and, when they enter naked, the girls are already bathing. They become angry and begin throwing bathing supplies at them. Zero Two runs out with their clothes and Hiro chases her. They meet on the roof where Hiro begins laughing after she throws their clothes in the air. She says she wanted to take part in a human fight.

Nana and Hachi scold the group after they get dressed. In the girl's room, Zero Two tells them if they half-ass things, they'll end up adults. She says to say what they want because they'll all die sooner or later before leaving.

Zero Two is among the parasites when they find Miku. When they wonder what the room is, Zero Two says that it's probably one of the rooms the former Squad 13 used. Zorome questions what happened and Zero Two says they were obviously wiped out.

Later on, Zorome and Miku are seen bickering before they enter their FRANXX. Hiro says that he wants get to know Zero Two better. She tells him to grab on and never let go of her.

Episode 09: Triangle Bomb
In the beginning of the episode, the members of Squad 13, with the exception of Zero Two, receive presents from Papa. When she sees Hiro's requested present is a book, Zero Two's attention is riveted, and she asks if it is a picture book. When he replies in the negative, Zero Two is shown to have a rather disappointed face.

Later that morning, Hiro presents her with an item that had once belonged to his former (and likely deceased) partner Naomi: A silver-finished hand mirror. He explains that he noticed Papa had given her nothing, and so as a result decided to make sure she also has a gift. Zero Two reacts by putting her arms around Hiro, thanking him for thinking of her.

As Squad 13 is sent on a mission against an airborne Gutenberg-class klaxosaur, Goro ejects Ichigo out of Delphinium to prevent her from perhaps being killed by the enemy's self-inflicted explosions. When the squad later returns to their sortie, Zero Two assists Ichigo in rescuing Goro by carrying her in Strelizia's hand, before slipping Squad 13's leader into the klaxosaur through its exhaust vent.

Episode 10: The City of Eternity
She and Squad 13 ventured into Cerasus Inner City but she's not amazed, remarking that the city's lifeless.

Episode 11: Partner Shuffle
She accompanies Squad 13 on a sortie against a Gutenberg-class Klaxosaur.

Episode 12: The Garden Where It All Began
Zero Two and Squad 13 returns to the Garden. She is anxious and came to the library with Hiro to find a picture book. She nearly sank her teeth in Hiro's neck but luckily, she was still conscious enough to realize what she's doing. Problems later arose as she goes on a killing spree. When she was ordered to return, she attacked other members of Squad 13 and strangled Hiro. Their minds merged through Strelitzia.

Episode 13: The Beast and the Prince
Hiro connects deeply with the consciousness of Zero Two and catches a glimpse of the memory that flows from there. It was a memory of their childhood, Hiro remembers that they had once met when she was nameless and unable to speak

Episode 14: Punishment and Confession
Zero Two and Hiro realize they knew each other as children. Zero Two catches Hiro before he collapses and asks if he's her darling from her childhood and is horrified thinking of what she had done. Ichigo suddenly interrupts and throws her off of him and into Goro. He asks if she's alright as Ichigo tries to revive Hiro. The other FRANXX wait. When they return to the docking facility, Hiro is taken for treatment. Zero Two realizes what Hiro meant when he said he wanted to understand her better.

Hachi announced they must neutralize every klaxosaur inhabiting Gran Crevasse. Nana says that it is a joint operation with the 9's and FRANXX squad from each plantation. He says that Squad 13 is schedules to be part of the sixth wave. Nana says it will be their most difficult mission and Ichigo raises her hand. She asks that Zero Two is removed from Squad 13 as of that mission and, if not, Squad 13 will not participate in the operation. Nana says that she was set to return to the 9's as of the mission anyway. Zero Two protests, but the parasites stop her from seeing him.

When Hiro gets up, he is stopped by Miku. Zero Two is also guarded and prevented from leaving her room. Ichigo comes in to see Hiro and they chat. She gives him an apple. She tells him that Zero Two is returning to the 9's the next night. She asks if he hates her and says that, even if he does, not to go anywhere.

Hiro apologizes and Ichigo cuts her thumb, so Hiro bandages it for her. Zero Two remembers what Ichigo said and thinks that she knew she could never be a human. Ichigo leaves the knife and apple peels. Zero Two breaks out of her room as Ichigo returns. She roughly throws Goro against a window. Ichigo scolds Zero Two and asks if she wants to lie to him again. She says she's wrong and just wants to talk to him.

Goro tells Ichigo to let her see him and Kokoro agrees, stating that it's sad to see them apart. Goro says that she can meet him, but they're all going to be there. When they enter the room, it's empty. Hiro had used the knife to make a rope out the curtains. He then tied the knife to it and climbed upstairs, escaping containment. Zero Two becomes enraged and says that they tricked her. Hiro unknowingly goes to Zero Two's room.

He asks through the door if she knew about their past. He opens the door to find the room destroyed. He returns to the hospital to find all his teammates unconscious and her attacking Ichigo. Zero Two, with a devious grin, invites Hiro to "talk lots and lots". Hiro scolds her for being such a monster. She realizes the damage she'd done to him.

Zero Two leaves the plantation as the other parasites watch her leave silently. She passes by Hiro without saying anything. When Ichigo suggests they go inside, she finds that he's crying. He is about to go after her, but Ichigo stops him, saying he'll turn into a monster. When he turns away again, she grabs his face and kisses him.

9'a greets Zero Two and presents her with the stamen that Dr. FRANXX brought for her.

Ichigo says she doesn't regret the kiss they shared during the mock battle and that she wants to be with him forever. Goro overhears this and sadly smiles. Ichigo says that he'd always been her everything and that she'd never been interested in anyone else. He looks up to see Zero Two's ship.

Episode 15: The Bird that Shares Wings
Her face is deathly pale, her eyes blood red and her horns long enough to touch the ceiling. Hiro tries to connect, but he gets no response. He holds her horns and asks to be taken to her. He later saw her memories.

She cannot remember things, but begins to when she recognizes familiar actions. She licks her wounds in a similar way. Seeing her book, she begins eating it. She learns the word "boku" and Zero Two, and "darling." She remembers him getting attacked and begins crying.

Zero Two's horns break and Hiro hugs her. She pushes him away and tells him not to look at her. They apologize and cry holding each other. He says they can see the world together and kisses her as she cries. Through their tears of joy, Strelitzia emerges, more powerful than ever and with inverted color schemes. She then completely annihilates the Super-Lehmann-class Klaxosaur threatening Plantation 13. They confess their love for each other. Futoshi and Zorome cry and Ichigo says she's happy for them. The 9's begin attacking as well.

Inside the mountain klaxosaur, they find that its core is a collective mass of cores. A large hand suddenly shoots up from the ground. 9'a laughs and says that it reacted quickly. It crushed the plantation (definitely not Cerasus), leaving behind a pile of debris. Squad 13 was lucky enough to still be standing as they stood between the hand's digit.

Episode 16: Days of Our Lives
In her room, Zero Two happily files her horns as she looks at herself using Naomi's mirror.

Later, Ichigo serves up their rations. When Zorome complains, Ichigo takes his rations and says he doesn't have to eat it. Ikuno enters and offers to help, but Ichigo says that it's fine and asks if her fever went down. Zero Two places her forehead on Ikuno and says that she's 36.7 degrees (a normal body temperature) but tells her not to push herself.

They pray for Papa before they eat, though Zero Two eats anyway. Zero Two lists off the chores and Miku, smiling, notes that she's meticulous.

...

Hiro and Zero Two walk together. Hiro says that Goro must have gotten child fever last week. Zero Two curiously looks at a plant. Hiro explains that they're sakura buds. He says that they're a really pretty color, like her hair. She giggles and says she wants to see them.

He asks how she felt about their lives and she says they're having fun and would like to live like that forever. He scooches closer to her and is about to hold her hand, but she suddenly remembers that she was supposed to go bathing with the other pistils. She tells him not to peek.

The girls bathe in the river. Miku asks if they seen Mitsuru's hair as she washes Zero Two's hair. Ikuno says that he looks pretty good. Zero Two sees a fish and is about to get it, but Miku stops her. Miku says that her hair's a pretty color, and Zero Two says that Hiro said so too. Miku pours water on her head and asks if they always talk about corny stuff. She tackles her and pushes her into the water. When she says that she'll wash hers, she notices that she has grey hair.

The parasites meet in their living room and Ichigo says that they have five sources they can use for drinking water. Mitsuru says that only two of them are only usable with filtering. Ikuno asks if they can repair the circulation system themselves. Hiro says that Mistilteinn doesn't have the equipment. Futoshi says that their access to the elevator is restricted too. Zorome asks why they don't send a letter to Papa and ask him to fix it. Goro says that he doesn't think there'd be a point. The parasites sadly reflect on their vulnerability, so Zero Two says that they should cook their own food. The others agreed

...

Ichigo welcomes Hiro, Goro, and Zero Two back from fishing. Zorome and the rest are impressed with the 11 fish that she caught. Goro caught 9 and Hiro, awkwardly smiled and scratched his head, saying he didn't catch any. Zero Two says she'll teach him later. The others want to try fishing as well.

Goro asks Ichigo how she is, and she says that the mood really changed. She happily watches as Zero Two tells the rest how to fish. Ichigo says that Hiro was right about her being a normal girl. She says she wants whats best for her and Hiro.

Futoshi says that they cried and laughed more than ever before.

That night, Kokoro and Miku sleep together. Zero Two draws pictures in her room of the book they read together. When Hiro says that it's a sad story, she says that it was her first "pretty thing." She met him and wanted to have something beautiful with him. She realizes now what it means to be human and they embrace.

They hear a klaxosaur scream as another horned girl is shown.

Episode 17: Eden
Ikuno holds a mirror for Zero Two as she files her horns. She asks if it hurts and she says not a bit at all. When she finishes, she tells Miku. She presents a flower headband and places it on her head. Zero Two asks what it looks like and Miku says perfect and that Hiro will love it. Zorome suddenly runs up and says there's a problem.

The Nines later arrived at Mistillteinn on Papa's order. 9'α and Zero Two had a private chat in the woods.

Smiling, 9'α asks how long she's going to play human since she'll never be the same as them. Though they're unique, they're imperfect unlike she and the other nines. She tells him not to call her "Iota" but "Zero Two." He asks if she's throwing away the Special Forces code name that Papa gave her. She says that her darling gave it to her and it's important. He begins laughing at her as she walks away. He wishes her luck, again calling her "Iota."

Zero Two looks at the flame of a candle in her room when Hiro calls out to her. He asks about her flower headband. She says that Miku made it for her. She shyly tells him not to stare, but says it's okay after he compliments her.

Zero Two pushes his bangs back to reveal small blue horns poking through his forehead. She says that they'd grown bigger. She thinks that they must be because he rode with her or because they drank eachothers blood. She sadly says that she drastically altered his destiny. He leans in and places his horns against her's. They kiss and rest their foreheads against each other. Blushing, Hiro says that it makes him happy to be more similar to her.

She tells him that she ate her old picture book when they were trying to erase her memories. She says that she started wanting to become human because she wanted to see him again and she was told that she could do that by killing klaxosaurs, though she realizes she shouldn't have believed them. Hiro asks if Papa and the rest told her, but she doesn't answer.

She asks that he show her the picture he drew. He refuses, so she playfully snatches it from him. She finds that he crudely drew a picture of a king. She begins laughing and he covers his face in embarrassment. She says that it's approved and she loves it as she holds it against her chest.

The next day, 9'α had been poking around and conflict arose as interrogates Kokoro on the childbirth book. A harsh exchange of words soon followed, with Ikuno slapping 9'α.

Hiro
Zero Two was enthralled by Hiro immediately after seeing him. They first meet when she was skinny dipping in Cerasus' lake. Being pleased with his taste and him not being afraid of her horns, she proposes that he become her "darling." Though they are briefly separated, they reunite after her partner dies and Hiro acts as his replacement. Their relationship becomes stronger with them both finding someone with whom they can successfully pilot with; being even able to pilot Strelizia in its iron maiden form.

As they spend more time together, Zero Two acts more flirtatious and teasingly towards Hiro, causing him to become bashful. Many of the things that she does seems foreign to the other parasites, such as sitting on Hiro's lap at the boys' table and feeding him. Their relationship is briefly strained after hearing of her past and seeing Mitsuru after riding with her, as Hiro becomes somewhat wary of her. He later realizes and confesses that he never really cared about riding the FRANXX, but wanted to ride with her.

After riding again with her, Hiro develops a tumor on his chest. Though Hiro could die, he feels that being useful to the others is more important than his life and thanks her for giving him the chance to pilot the FRANXX. Zero Two reaffirms that she is his partner and she alone. Zero Two then unzips his uniform revealing a pulsating blue klaxosaur tumor growing out of Hiro's chest. She reminds him that non of her partners have ridden with her more than 3 times. She ask him if it hurts, and relates that the pain must be unbearable, however she states "it looks beautiful". Zero Two poses Hiro that if he wants "off this ride" now's his chance. Unyielding, He declares "I'll ride with you!". Zero Two becomes overjoyed and begins laughing and dancing by the lake.

During the next battle, Strelizia flies into battle to help the other parasites. In the midst of combat, Hiro's tumor intensifies causing his engorged veins to show through his battle suit and spread to face. This causes their performance to slump and lag, prompting Zero Two to rile him up, this proves effective as Hiro pulls himself together and continues the fight.

Once all the Conrad-klaxosaurs have been annihilated, Squad 13 shifts priority to Target Beta which has taken a humanoid-form. Squad 13 immoblizes the titan while Hiro flies the Strelizia into the sky. He begins to pour what energy he has left into a downward thrust in hopes of killing it. The attack seems successful causing Target Beta to collapse. Hiro appears to have died causing the Strelizia to deactivate and go into Stampede.

In his death-like state, Hiro is greeted by Naomi. He subsequently sees Zero Two. Wondering if she came to say goodbye to him, He reaches out to her. However, Zero Two sadly turns away mirroring the beginning of the episode. Hiro wakes up and sees Zero Two desperately trying to fight of Target Beta. He desperately tries to tell Zero Two not to fight alone, in doing so, she'll cause her own death. Hiro then recalls that Zero Two is a monster and that she's been all alone. Zero Two can't "fly" by herself after all. Zero Two lets out a groan in pain then a newly revived Hiro grabs her from behind and calms her down. Zero Two eyes return from red to cyan and ask if it's really him. Hiro reminds her that he is her partner, and that he'll never leave her alone. The Strelizia's Iron Maiden form is then restored.

Hiro and Zero Two's relationship continues due to him surviving after his third time piloting with her. While at the beach on Squad 13's day off, Zero Two teases Hiro thinking she would kiss him again. When Zero Two had stolen the other Parasites clothing, Zero Two playfully taunted Hiro, telling him to catch her, or saying he has to do better, laughing as he chased her around the house. On the day the Parasites received presents, Hiro, feeling bad that everyone else got presents, gifted Zero Two with a hand mirror that was left behind by Naomi, with Zero Two thanking Hiro with a surprise hug.

Starting at episode 11, Hiro and Zero Two's relationship starts to dip, with Hiro asking Zero Two to open up to him if anything was weighing on her mind, however, she brushes his request off, calling it a pain. During the fight with the Klaxosaur collective, Zero Two expressed anger when Hiro had stopped her from attacking it, even though he also saved them from getting possibly crushed under its foot.

Episode 12 is where their suffering relationship begins to show, during the fight with Klaxosaurs, Hiro repeatedly bickers with Zero Two, saying they need to cooperate with the others, but his pleas fall upon deaf ears, And Zero Two annoyed that Hiro is also "getting in her way".

Later, at the lake in Mistilteinn that same episode, Hiro finds Zero Two biting her fingers, expressing concern, and asking what she means by "wanting to become human." In an effort to make her snap out of her state, Hiro desperately confesses his feelings for her, she, however brushes it off and pushes him to the ground, thinking he means it in a different manner, then stating that she will teach Hiro what comes after kissing, unbuttoning her uniform. When this did not work, Zero Two, in her off state, claims this isn't enough, telling Hiro to kill more Klaxosaurs to turn her human, calling him her Fodder.

During the episodes climax, as Zero Two maddeningly fights klaxosaurs, Hiro pleas that what she is doing will not satisfy her wish, fed up with Hiro, Zero Two commands that he should be quietly devoured like the fodder he is, taking complete control of Strelizia, causing it to enter its Stampede Mode. Zero Two begins to strangle Hiro, telling him to give her all of his life. Then stating that she will become human so she can meet her "Darling from back then" which, unbeknownst to her, was actually Hiro all along.

In Episode 13, it's revealed Hiro and Zero Two had already met each other before as children. Hiro helped her escape from a parasite experimentation laboratory after witnessing APE cruel experimentations on her. While they were on the run, Hiro named her Zero Two, helped her learn many things and molded her personality. He eventually promised he'd marry her and become her Darling, making Zero Two cry out of joy and hug him. Unfortunately, APE officers managed to catch them and wipe their memories away. After recovering their once lost memories through syncing in Strelizia, Zero Two and Hiro stare at each other with tears in their eyes, realizing they have finally found their lost love.

However, in Episode 14, after Zero Two beats each and every Squad 13 members, Hiro calls Zero Two a Monster. Deeming this as a punishment for what she did to Hiro, Zero Two leaves his side.

In Episode 15, having refused to give up on Zero Two. Hiro recklessly goes to the battlefield while using Training unit. After his Training unit destroyed, Hiro temporarily use Delphinium to forcefully enter Strelizia Stampede. There, Zero Two was consoled and even kissed by Hiro. Finally realizing that Hiro will be always at her side no matter what, Zero Two reciprocates Hiro feelings towards her.

Hiro speculates that he was able to pilot with Zero Two over three times due of him licking Zero Two's bleeding knee, allowing Hiro to adapt his body to Zero Two's Klaxosaur aspect.

In episode 16 and 17, they had fun together drawing Zero Two's "first pretty thing". They also talked together more.

Ichigo
Zero Two finds Ichigo bossy, even annoying. However, she does acknowledge the tension between them stemming from Ichigo's unrequited love towards Hiro, and takes visible pleasure in taunting her about their closeness. Ichigo is grateful that Zero Two saved her life and those of her squad, however, she also harbors resentment towards Zero Two due to her attitude and relationship with Hiro. This results in altercations between the two whenever they come face to face. Over the course of the series, Ichigo becomes saddened, which progresses toward depression due to her desire to be with Hiro combined with the fact that they are incompatible and Zero Two's attachment to him. Despite this, Ichigo welcomes her to the team after their battle together and even confronts 9α that she prefer battling together with Zero Two rather than with Nines. When Zero Two helps Ichigo rescue Goro, she is happy when Ichigo says that she trusts her, and admits that she doesn't dislike helping her out. Zero Two has also said that she likes Ichigo's taste after licking her cheek, much to Ichigo's discomfort.

Eventually, Ichigo become fed up to Zero Two and hated her very existence, mainly due to her jealousy that Hiro always had his view to Zero Two and not her. In episode 14, Ichigo won't allow Zero Two and Hiro to meet with each other and proposed to Nana that unless Zero Two is kicked out from Squad 13, they won't participate in next mission. Later, Ichigo is beaten by Zero Two due of Hiro absence when she, after discussing with Goro, reclutantly allow Zero Two to visit. After Zero Two gets deported for her actions, Ichigo tells a bewildered Hiro that this is for the best.

In Episode 15, Ichigo, finally realize Hiro unwavering feelings for Zero Two, deliver Hiro to Zero Two using Delphinium.

Goro
Goro once commented that she wastes her "good looks" with her vicious eating habits. He seems to have a form of animosity towards Zero Two (mainly stemming from her dynamic with Ichigo) and his fear of her possibly causing Hiro's death.

Goro admires the relationship that Hiro and Zero Two share and secretly contemplates if he can share that with Ichigo. When they go to the beach, Goro passes a skewer to Zero Two. After initially shocked, she accepts and silently analyzes it.

Goro is the only one who treats Zero Two as an ally beside Hiro. In Episode 14, Goro convinces Ichigo to let Zero Two meet with Hiro, only to find Hiro gone missing. Although Goro tried to reason with Zero Two about this, Zero Two won't listen as she feel deceived by them.

Miku
Miku initially feels uncomfortable with Zero Two because of her personality and horns. She later thinks that Zero Two and Hiro make a good couple which makes Ichigo uneasy. Zero Two (Strelizia) and Mitsuru rescue Miku (Argentea) and Zorome after their mission underground goes awry. The timely arrival and entrance of the Strelizia allows them to escape while the Strelizia goes on a massacre. When they go to the beach together, Miku and Kokoro express their excitement that Hiro and Zero Two are now officially part of Squad 13. Miku tells Hiro that he and Zero Two better put in Naomi's share of the work.

Zorome
Zero Two doesn't think much of Zorome. Zorome on the other hand exhibits a form of envy towards Zero Two and Hiro. Zorome is very verbal about this, taking a toll on Miku. It may be inferred that Zorome would like to ride with Zero Two and/or get the same treatment she gives Hiro. Zorome also doesn't like it when she obviously ignores him and rejects him.

Zero Two rescues him, Goro (Delphinium), and Futoshi (Genista) during their mission into the underground that went wrong. Zorome is in awe of Zero Two's daring rescue and and is visually relieved. Zorome is jealous of Zero Two and Hiro acting like a couple and wishes he had a girl like that. He wants to know what Zero Two means by "kiss" and "loving a person."

Kokoro
Kokoro finds her a "strange person and wonders if she likes sweets". Kokoro is very quiet and reserved, but is fond of Zero Two and finds her presence reassuring. Zero Two rescues her, Ichigo (Delphinium), and Miku (Argentea) during their mission into the underground. After the retrieval of the deactivated Strelizia, she is visibly worried when she sees Zero Two emerge from the FRANXX but not Mitsuru, who was at a near-death state in the cockpit. She emulates Zero Two when feeding Futoshi in the same manner Zero Two feeds Hiro. Koroko and Miku are excited to that Zero Two and Hiro are now part of Squad 13. Kokoro expresses that it's reassuring since Zero Two has saved the squad in every mission.

Futoshi
In "Episode 1: Alone and Lonesome!", Zero Two saves Futoshi and the other Parasites from the klaxosaur attack during the welcoming ceremony. After the battle he looks on as she not only exits the Strelizia but that she is also carrying an unconscious Hiro out with her. He inferred that Hiro piloted the Strelizia

In "Episode 2: What it Means to Connect!", Futoshi is amazed that she is "nothing" like the rumours.

In "Episode 3: Fighting Puppet!", Zero Two rescues him and Kokoro (Genista) from the underground klaxosaur swarm.

In "Episode 4: Flap Flap!",  Zero Two rescues Futoshi and Kokoro (Genista) from the giant razor-like snake klaxosaur, after the mission went wrong and HQ sacrificed them so that the carrier can escape.

In "Episode 5: Your Thorn, My Badge!", Zero Two takes Futoshi's seat at breakfast beside Hiro. Forcing him to sit with Kokoro at the girls table. This turns out to benefit Futoshi as well as Kokoro feeds him, mimicking the relationship of Zero Two and Hiro.

I n " Episode 7: Shooting Star Moratorium! ", Futoshi is glad that Hiro and Zero Two are now officially a part of Squad 13. He acknowledges that Zero Two always saves them and they wouldn't be there without them.

Ikuno
Ikuno notes that she is a klaxosaur hybrid. Ikuno also chagrins the fact she has a single digit code. Ikuno is visibly hurt that Mitsuru would rather ride with Zero Two after their failure to launch the Chlorophytum. She is later seen angrily watching Mitsuru blame her for the failure and proposing that Zero Two take him on as her official partner. Zero Two rescues Ikuno (Chlorophytum) and Mitsuru from the giant razor-like klaxosaur after HQ sacrifices them in order for the carrier to escape.

Mitsuru
In "Episode 3: Fighting Puppet!", Misturu volunteers to be her temporary partner. The result leaves him bloody, broken, and on the brink of death. He becomes fearful of her, stating anyone that willingly wanted to pilot with her was insane. It is not known what actually happened to him, but from his perspective she tried to 'devour his body, blood, and soul'. And while she was doing it, she was smiling. Mitsuru is the only one visually displeased with the official welcoming of Hiro and Zero Two into Squad 13.

Nana
Nana is Zero Two's handler from HQ, and Papa. She transmits orders to Zero Two and whether or not she has the proper authorizations. She and Zero Two have a passive aggressive (or just aggressive) relationship, however, they are particularly chummy on occasion. They share a degree of respect for each other as they make concessions that others do not enjoy. Zero Two is known to ignore or directly disobey orders from Nana when she sees fit to do so.

Zero Two asks Nana whether there's an ocean in Plantation 13, to which Nana asks why she can't take a simple shower. Zero Two licks herself, expressing she hates how she "tastes". Later after disembarking into Plantation 13, Zero Two disappears unknown to Nana's knowledge. Zero Two is then shown mocking Nana as she plays with her cap then tossing it aside.

Later, Nana reprimands Zero Two for running off and orders her not to mix with the Parasites. After the klaxosaur attack, Nana informs the Parasites of Zero Two's background and reputation.

Nana commands Zero Two to sit at the table she's "supposed" to be sitting at, instead of mixing with the Parasites. Later in the elevator Nana tells Zero Two not to mess with the parasites as she is "Too much for them to handle". During the discussion of Hiro's parasite promotion, Nana vetoes Zero Two's proposal informing her that HQ hasn't authorized the use of Strelizia.

While Nana is coordinating the seemingly successful mission in the super pipe, Zero Two suddenly appears in the room and begins to mock them that it's not over yet. Zero Two was right as a swarm of Conrad-class klaxosaurs emerge from the shadows of the underground and begin to overwhelm the FranXXs. As the situation becomes dire, Zero Two continues to jest Nana into letting her pilot the Strelizia with Hiro, but Nana does not bend. Zero Two and Nana begin to butt heads, before the tension escalates any further Mitsuru intervenes and volunteers to pilot the Strelizia, being the only available "official" stamen. Nana asks Zero Two whether she could ride with Mitsuru. Zero Two persists that she will only ride with Hiro. She then looks over to Hiro to coax his affirmation, but Hiro tells Zero Two to ride with Mitsuru. He states that he'd rather have his teammates saved than be able to pilot a FranXX. Nana then coordinates the deployment of the Strelizia.

Later, Zero Two (Strelizia) decides to go on a rampage rather than comply with Nana's order to withdraw. Nana then deploys a team to "retrieve" the Strelizia and her Stamen. After the retrieval, Nana grimly looks at the sight of Zero Two as she exits Strelizia without her stamen.

Etymology

 * Her codename can be read as "oni": "o" from "0" which can be written as "○" in kanji and  ni  from 2. Oni means "demon," a reference to pair of horns on her head.

Quotes
"Oh, Found one."

- Episode 1, when she spots the lake next to Hiro from the carrier

"I'm always alone too, thanks to these horns."

- Episode 01

"If you don't belong here, just build a place where you do."

- To Hiro

"Your taste makes my heart race."

- To Hiro

"Found you, my darling."

- the ending scene of Episode 1 where she drops Hiro outside the cockpit of the Strelizia and happily smiles at him.

"Here, this is nice and sweet!"

- the Episode 2 pouring honey over Hiro's breakfast.

"I feel like I'm gonna suffocate in here"

- Quoted from Episode 2 while she's riding the elevator.

"You are just like me."

- To Hiro

"I like the look on your eyes, it makes my heart race."

- the dialogue before their first flight together when she sees Hiro's tears during Episode 2.

"I'll let you have him this one time. Go for it!"

- Episode 2 when she "allows" Ichigo to have Hiro ride her.

"Once we die, we'll only be a statistic. It won't matter what we're called."

- Episode 3 while she's out onto the ledge.

"Just look at this lifeless city. There are no skies or oceans here. It's a one-way street to nowhere. A dead end life."

- Episode 3 when she's overlooking the inner city.

"Darling, wanna run away with me? I can get you out of here."

- Episode 3 when she was with Hiro on the balcony overlooking the city.

"Do you think I’m a monster too?"

- Episode 4 when she confronted Hiro in the bath.

"How can I leave after hearing that?"

- Episode 4 when she's about to escape.

"Nobody's ever said such embarrassing things to me before!"

- Episode 4 after running away from her Guards and towards Strelizia together with Hiro.

"You wanna ride me, huh?"

- Episode 4 after Hiro's confession.

"Of course you can do this. WE can do this!"

- Zero Two reaffirming Hiro he can pilot a FranXX it as long as it's "them".

"Weaklings die, Big deal."

- Episode 5, Zero Two saying that to a member of Squad 26 that she doesn't care about his partner dying

"Sure, he could. But that'd mean he didn't amount to much."

- Episode 5, Zero Two concerning the possibility Hiro dies.

"What is "human" to you people?"

- Episode 5 after Ichigo slaps her and vilifies Zero Two for not being "human".

"Your partner is me, and me alone"

- Episode 5, Zero Two responding to Hiro thanking her for giving him the opportunity to pilot a FranXX.

"What'll it be, if you want off this ride, now's your chance."

- Episode 5, Zero Two asking Hiro if he's still willing to ride with her even if it means leads to his death.

"Swimming in the ocean feels so good! And it does taste salty"

- Episode 7, Zero Two's 1st experience with the ocean.

"You're my wings right? If I'm with you, I can fly anywhere I want... We'll always be together right?"

- Episode 7, Zero Two embracing Hiro in the ocean.

"A kiss is something you share with your special someone, is the one you kissed special to you?"

- Episode 7, Zero Two explaining "the kiss" to Ichigo.

"Kill more and more of those monsters and make me human. You're only my fodder, after all!"

- Episode 12, Zero Two talking to a desperate Hiro.

"Give me all your life. I'm going to become a human. So i could meet my darling from back then."

- Episode 12, Zero Two strangling Hiro while rampaging

"The leaving something behind part. My body can't do that. It's wonderful. You're all wonderful. You have the ability to decide your futures with your own hearts." - Episode 17; Zero Two talking about her thoughts on reproduction.

Trivia

 * Her theme is "Awakening" by Tachibana Asami.
 * The final boss of Kirby 64: The Crystal Shards is also known as "Zero Two".
 * Zero Two is the one of the only members of Squad 13 whose name wasn’t given to her by Hiro, the other being Ikuno, whose name was given to her by Ichigo
 * Zero Two’s other name, Iota, was given to her by her previous squad, but she dislikes her previous squad and the name they gave her, so she gave herself the name “Zero Two”, based on her code name: “002”.
 * Zero Two and the Klaxosaur Princess share very similar code names, the Princess being “Code: 001”, and Zero Two being “Code: 002”.
 * Zero Two and the Klaxosaur Princess are the only known Klaxosaurs with code names.
 * They are also the only known Klaxosaurs with humanoid appearances.

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