Squad 13 is a group of Parasites who are the main characters of the series. The squad consists of ten children who are 14-years-old, and are based out of Plantation 13 living within their home area, Mistilteinn, which is colloquially referred to as the ‘Birdcage’. Their caretakers are Nana and Hachi.
Squad 13 is unique most notably for their individually designed FRANXX but also because they refer to each other by names rather than their code numbers. Their names are based on Japanese readings of their code numbers. They are considered a temporary experimental team hastily created by Dr. FRANXX to rediscover humanity’s previous emotional and reproductive instincts.
After spending their entire childhoods in the Garden and undergoing training to become pilots, ten children are discharged and assigned to Plantation 13 based on their capacity and aptitude results. They are paired up in boy-girl partners; the pairs are: Hiro and Naomi, Goro and Ichigo, Zorome and Miku, Futoshi and Kokoro , Mitsuru and Ikuno.
They are given a capacity test in order to determine if they are qualified to become official parasites. All but Hiro and Naomi pass and participate in a graduation ceremony hosted by Papa, who praises them for their loyalty and dedication to protect the adults. Zero Two is brought to the plantation after failing to get along with her former squadmates, the 9's. Due to failing their capacity test, Hiro and Naomi are obligated return to the Garden, although Hiro, who is deemed a prodigy, is offered to stay. However, during the squad’s startup ritual, a Klaxosaur attacks the plantation, which severely injures Naomi in the process. Zero Two abruptly fights it with Strelizia in stampede mode but her partner is mortally wounded. Hiro is able to successfully synchronize with Zero Two and they quickly kill the klaxosaur. Naomi is sent to the hospital and everyone assumes she returns to the Garden. Hiro is interested in partnering with Zero Two because she is the only pistil he is found to be compatible with but she is not allowed to formally join the squad because her partners always die after piloting three times with her, as her klaxosaur genetics cause her to subconsciously devour her partners.
During Squad 13’s first mission, Delphinium (piloted by Ichigo and Goro), Genista (piloted by Kokoro and Futoshi), and Argentea (piloted by Miku and Zorome) are dispatched to neutralize a Conrad-class Klaxosaur on the outskirts of the plantation while Chlorophytum stays behind due to Mitsuru and Ikuno failing to connect. The three units, however, are accosted by more Klaxosaurs than expected, and Hiro and Zero Two offer to be sent as backup but Nana refuses because Hiro is not an official stamen. Mitsuru offers to go with Zero Two instead and is reluctantly approved by Hiro, Zero Two, and Nana. However, Mitsuru becomes empowered by the experience and Zero Two decides to test him. At the end, he is found to be gravely wounded and traumatized. As a result, Zero Two is ordered to return to the front lines alone. However, she and Hiro disregard this and proceed to pilot Strelizia a second time to defend the plantation from another Klaxosaur. After this, APE allows Zero Two to remain at Plantation 13 but only because Strelizia will be a necessity for the still inexperienced squad.
The other squad members are initially hesitant to accept Zero Two as a member due to her reputation but gradually come to consider her as a comrade due to having Strelizia as a necessity. Goro, Futoshi, Miku, Kokoro, and Ikuno find no reason not to accept Zero Two as she and Hiro have a positive influence over each other but Ichigo, Mitsuru, and Zorome are reluctant; this is due to Ichigo’s feelings for Hiro and her jealousy of Zero Two, Mitsuru is afraid of her after she seemingly tried to kill him earlier, and Zorome is still wary of her reputation. Due to the klaxosaur attack from the startup ritual plummeting large amounts of magma energy, Plantations 13 and 26 are linked to transfer magma energies but Squad 13 is assigned to a duo with Squad 26 as the high amount of magma energy will attract more Klaxosaurs. Strelizia is dispatched to assist as a standby to protect the plantations. Since his first ride with Zero Two, Hiro begins suffering from a large blue tumor growing in his chest but keeps it a secret from the others. Goro finds out and wants Hiro not to pilot Strelizia again, as it will be his third ride, but Hiro refuses to concede. The plantations are later attacked by a horde of Conrad-class klaxosaurs and then a Gutenberg-klaxosaur. Both squads initially struggle and Hiro slowly begins to succumb to the effects of his illness, causing his connection with Zero Two to sever and Strelizia to enter stampede mode. However, as he lays dying, he finds the willpower and resolve to continue fighting to live, and reconnects with Zero Two.
With Hiro and Zero Two’s reconnection, the squads emerge victorious when Strelizia eliminates the Klaxosaur. Due to this victory, Squad 13 is awarded a trip to the beach, which is their first experience outside the plantation and they discover an abandoned modern city, leading them to wonder about previous human civilization. The squad then begins to enter puberty and goes through a ‘gender conflict’ after the girls’ parasites suites melted in front of the boys during a battle. The girls, led by Miku, split the house from the boys. However, after they learn there was a previous Squad 13 that was killed, everyone reconciles. Squad 13 is dispatched to stop a Gutenberg-klaxosaur from colliding with the plantation but a disadvantage causes Goro to eject Ichigo from Delphinium and contemplate self-destruction to save everyone and the plantation. However, Ichigo reaches him in time to help him escape and he confesses his feelings to her, although he doesn’t expect a response due to her being in love with Hiro.
APE awards the squad with medals for their significant victories and the children visit the city for the first time. Overtime, the squad’s killing record drastically increases and they are deemed qualified for missions only given to special elite squads. According to Nana, the parasites growing into adolescence and enduring their problems together is what motivates them to bring out their full abilities. Due to Mitsuru and Ikuno’s incompatibility, their paracapacity level is shown to be low and Nana fears Mitsuru may become a ‘pruning target’ as he is shown to be the source of the issue, and she proposes the squad try a ‘partner shuffle’; they may choose another partner they deem is more appropriate. Ikuno tries with Ichigo but the two fail to connect. Kokoro volunteers to partner with Mitsuru and they are able to connect and become official partners. Ikuno pairs up with Futoshi. During a battle, Mitsuru’s recklessness almost causes him and Kokoro to get killed and Futoshi has to protect them while Kokoro talks with Mitsuru about his problems and help him reconnect with her. Zero Two’s relationship with the squad begins to deteriorate as she becomes more desperate to kill as many klaxosaurs as possible to “become human” and meet a boy from her childhood.
The squad is sent to the Garden to undergo tests and they learn Naomi was never sent back to the Garden. When a Klaxosaur attacks the Garden, Zero Two acts out violently against it, and Hiro is unable to control her and the squad begins to fear her when she aims her violence at them. During another battle, Zero Two attempts to kill Hiro, who enters her consciousness and realizes he met her when they were children and helped her escape from the Garden before they were captured and their memories were erased. Zero Two realizes Hiro is the same boy and is instantly remorseful of her actions. Ichigo further alienates Zero Two by openly referring to her as a monster and bans her from seeing Hiro, leading Zero Two to attack the squad in anger. She later feels guilty when Hiro calls her a monster and she decides to leave. A remorseful Hiro tries to stop her but Ichigo confesses her feelings to him and begs him to leave Zero Two for her.
The Squad is assigned to to the 6th United Company in the siege of the Gran Crevasse. Squad 13 fights alongside Squad 26 and the 9's. When a Lehman-super Klaxosaur begins rampaging on the plantation, Squad 26 self-destructs to stop it but the Klaxosaur survives and attacks Plantation 13. Squad 13 and the 9’s struggle to defend it while Strelizia fights in stampede mode. Hiro, while struggling with what to do, remembers his past with Zero Two and decides his love for her is too great for him to ignore, and he refuses to give up on her. He rushes to the battlefield and, with Ichigo’s reluctant help, reaches Zero Two. They begin to talk and they reconcile. The rest of the squad, wanting to see Hiro happy, also reconcile with Zero Two and truly welcome her into the squad. The team’s reconciliation with Zero Two proves instrumental in their dangerous battle against the super Lehmann klaxosaur, which they miraculously survive and win, and they open the doors of the Gran Crevasse. However, Plantation 13 is destroyed and only Miltiteinn remains intact. Hiro and Zero Two begin an official relationship and, unbeknownst to the others besides Zero Two, Hiro begins developing klaxosaur characteristics, such as horns and fangs.
Unknown to them, they are left alone at their boarding house for a month as part of an experiment to test their emotional responses with each other. During this period, the children begin to enjoy their first sense of independence despite their shortage of food and supplies, and discover concepts they were never taught. Ikuno reveals to Ichigo she is in love with her but struggles with her feelings. Kokoro and Mitsuru start to fall in love and she reveals she knows about sexual intercourse and childbirth, both of which are banned concepts, admitting she wants to bear a child and live a life beyond piloting the FRANXX. She and Mitsuru begin a romantic and sexual relationship, and decide to get married before the squad is scheduled to report to the Bird Nest. The 9's are sent to check on the squad and report to Papa about the relationship between Kokoro and Mitsuru, as intimacy between parasites is strongly prohibited. On the day of their wedding, APE apprehends them and erases their memories as punishment. Finally realizing parasites are not entitled to their own happiness, Hiro confronts Papa and demands the squad be released from duty, which Papa agrees to do on the condition they win the final battle at Grand Crevasse.
The squad agrees to this and arrive at Gran Crevasse to battle a horde of klaxosaurs. Hiro and Zero Two are tasked with using Strelizia to control Hringhorni, or the ‘Star Entity’, a massive Klaxosaur weapon within the facility, while everyone else serves as support. In midst of the battle, the klaxosaur princess manages to severely injure Zero Two and forcibly connect with Hiro to take control of Star Entity. A massive armada of spaceships appear and the Klaxosaurs stop fighting. Papa then reveals he and some of his companions are members of VIRM and have been using mankind against the Klaxosaurs. Although confused on who the real enemy is, Squad 13 decides to return to Grand Crevasse to help Zero Two rescue Hiro. After the two reconnect, due to the princess relenting to let the two stop VIRM and save the planet, they force VIRM to retreat but Zero Two is left catatonic.
Squad 13 is tasked with helping the surviving parasites recover from the confusion and trauma, and they begin attempting to grow crops to survive but learn magma drilling has left the soil deprived of natural resources. The children are also faced with the conflict of making their own decisions, especially when Kokoro finds out she is pregnant, and she and Mitsuru struggle between abortion or keeping the baby. Hiro deduces Zero Two is mentally fighting VIRM in space with Strelizia and decides to rescue her, although he is warned it will be a suicide mission. Goro especially advises him against it but Hiro’s resolves doesn’t waver because he says he can never forgive himself for leaving her behind. The squad then decides to accompany Hiro in his mission because they say the squad is not the same without Zero Two and they personally want revenge against VIRM. Mitsuru decides not to go because he wants to be there for Kokoro, whose pregnancy prevents her from piloting, and reconcile with her. The surviving members of the 9's accompany them as well and even sacrifice themselves to help Hiro reach Strelizia. At the same time, Kokoro and Mitsuru reconcile after he proves his resolve to be there for her and their child. After Hiro and Zero Two reconnect, they emerge victorious against the VIRM but large armada of it escape. Armed with a klaxosaur bomb, they travel through a warp gate to find and destroy the surviving VIRM while the rest of the squad returns to Earth to begin rebuilding society and the planet.
Over the next two years, many events unfold for the parasites; Kokoro gives birth to her and Mitsuru’s daughter, whom Mitsuru names Ai. Naomi is found have been in a cryogenic sleep in Dr. Franxx’s laboratory and she is rescued along with other missing children, and the parasites begin harvesting crops from fresh soil from the plantations. Hiro and Zero Two eliminate numerous armadas of VIRM before reaching the VIRM home planet. They are almost defeated when their connection is severed until Squad 13 senses something is wrong due to Ai’s intuition and begin sending their prayers to the two. Hiro and Zero Two hear their thoughts and reconnect, and plant the bomb into the VIRM's home planet. To safeguard the lives and future of their friends, Hiro and Zero Two sacrifice themselves and detonate the bomb while vowing they will meet again on Earth as long as their souls exist. Everyone later mourns their deaths.
During the next eight years,
the squad disbands, as the parasites become busy with their personal lives, and devote themselves to develop a self-sufficient lifestyle and allow the world to prosper. Ikuno works hard to develop a cure for the accelerated aging process of the parasites and she succeeds, although this leaves her sickly and bedridden. During a school entrance ceremony, the squad reunites and are shown to be living happily; Goro, who is a traveler, and Ichigo are married and expecting their first child. Kokoro and Mitsuru are still happily married and have four children. Miku and Zorome are teachers for the next generation. Futoshi is a baker and married with three children. Ikuno is a doctor and in a relationship with Naomi. The squad gathers at a cherry blossom tree to remember Hiro and Zero Two, thanking them for the lessons they learned from the two and their sacrifice to give them the freedom to live good lives.
A thousand years pass, when Hiro and Zero Two’s souls return to Earth and are reincarnated into two children who meet at the cherry blossom tree.
Hiro - The male protagonist. He is considered a prodigy by the adults but he struggles to find his purpose in life after failing to pilot and become a parasite until he piloted with Zero Two and was found to be perfectly compatible with her. He becomes Zero Two’s official partner. He has known Zero Two since childhood but his memories of her were erased after he attempted to run away with her. He is deeply in love with her and he is determined to be with her forever. He is the one responsible for giving all the parasites names and has a strong interest of the outside world. Once he finally regains his lost memories, he becomes determined to free everyone from APE’s control after witnessing the brutal treatment of the parasites. He dies after sacrificing himself to save his friends and the planet from VIRM and he is later reincarnated.
Zero Two - The female protagonist. She is a klaxosaur-human hybrid as a result of Dr. FRANXX’s experiments. Rebellious and mischievous, she takes delight in teasing others and has knowledge of the outside world other parasites lack. She has a dark past and is infamously referred to as the Partner Killer, due to her partners dying shortly after piloting with her, with Hiro being the only exemption. She has a rocky relationship with the squad due to her reputation and her initial coldness towards them at first. Once she is officially enrolled into the squad after Hiro becomes her official partner, she is gradually is accepted and she develops a closer relationship with the squad. She is deeply in love with Hiro and is determined to stay with him forever. She sacrifices herself with him to protect the planet and their friends from VIRM and they are later reincarnated.
Ichigo - The leader of the squad. She is a childhood friend of Hiro, Goro, Ikuno, and Mitsuru. Bold and emotional, she is not well-liked by her squadmates for her bossy attitude and she demands they always follow her orders no matter what. However, she values the welfare of her squadmates above anything else and she is willing to put her feelings aside for the sake of the others. She is in love with Hiro, whom she worries after he pairs with Zero Two, whom she shows jealousy towards. However, she later accepts the pair after realizing how important Zero Two is to him. She eventually falls in love with Goro after he kisses her. They later get married and have a child. As an adult, she finishes Zero Two’s picture book.
Goro - He is Ichigo’s partner. He had been close friends with Ichigo and Hiro since childhood. He tends to be optimistic and friendly due to wanting to avoid conflict, and he is considered to be the second unofficial leader of the squad for these characteristics. He is more mature than the other boys. He is in love with Ichigo but he doesn’t pursue his feelings due to her feelings for Hiro and he finds contentment in with the friendly relationship the three of them share. He eventually confesses to her but he doesn’t ask for a reply. He is concerned for Hiro after the latter pairs with Zero Two but supports their relationship. After he kisses her, Goro and Ichigo later get married and have a child. As an adult, he becomes a traveler.
Zorome - He is Miku’s partner. He is an immature, loud, and arrogant parasite who often argues with the others. He shows disdain towards those with double and single digit code numbers, particularly Hiro. He has no qualms about starting fights with his squadmates in order to prove he is better than them but it is shown that he truly cares about them and he will defend them. His dream is to become an adult and he shows admiration for Papa. Although he has quarrelsome relationship with Miku, he cares deeply for her and strongly hints that he has feelings for her, as he refers to stays partners with her and he doesn’t like seeing her in pain. As an adult, he becomes a teacher.
Miku - She is Zorome’s partner. She is brash, loud, and direct who has no qualms about speaking her mind. She has been close friends with Kokoro since childhood. She had a strong need to appear cute and has an open interest in boys. However, she is disgusted with anything she considers perverted. She has a strong dislike towards Ichigo but she has deep respect for Papa and the adults. She has a complicated relationship with Zorome. The two argue frequently but she strongly hints she has feelings for him, as she admits she cares for him the most and only she can put up with him. As an adult, she becomes a teacher.
Mitsuru - He was Ikuno’s partner and later became Kokoro’s partner. He has known Hiro since childhood and used to admire him until a misunderstanding over a broken promise caused him to hold a grudge against Hiro for a long time. Cynical and aloof, he showed indifference towards his squadmates unless he had to fight alongside them. Due to his incompatibility with Ikuno, he pairs up with Kokoro. He later learns it wasn’t Hiro’s fault for breaking their promise, and the two reconcile. He falls in love with Kokoro and they begin an intimate relationship. During their wedding, they are arrested and their memories are altered as punishment. He later finds out she is pregnant with his child, and they reconcile. Mitsuru and Kokoro form a happy marriage and have four children. As an adult, he works in farming and mechanical engineering.
Kokoro - She used to be Futoshi’s partner and later became Mitsuru‘s partner. She has been best friends with Miku since childhood. She enjoys taking care of the greenhouse of Mistilteinn and had an interest in the language of flowers. After finding a baby book, she becomes fascinated with it and yearns to become a mother to leave behind a legacy. She treats her squadmates with kindness but hides her own feelings. She is deeply in love with Mitsuru and she pursues her feelings for him by becoming his partner and helps him with his problems. After forming a relationship, they hold a wedding ceremony but are arrested and their memories are altered. She later finds out she is pregnant with his child, and they reconcile. Kokoro and Mitsuru form a happy marriage and have four children. As an adult, she becomes a florist.
Futoshi - He used to be Kokoro‘s partner and later became Ikuno’s partner. He is an overweight parasite who eats all the time but it is revealed he secretly suffers from bulimia. He is calm and friendly, which makes him likable among the squad. He is good friends with Zorome, despite the latter’s tendency to joke about his weight. He is infatuated with Kokoro and considers himself to be her protector. However, after she breaks their partnership and makes it known she doesn’t reciprocate his feelings, he is devastated and shows jealousy towards Mitsuru. He later accepts them as a pair because he wants Kokoro to be happy. He later marries unnamed former pistil and has three children. As an adult, he becomes a baker.
Ikuno - She used to be Mitsuru’s partner and later becomes Futoshi’s partner. She is calm and insightful, and maintains an air of poise. She has been close friends with Ichigo since childhood, and she is secretly in love with Ichigo. She despises the boy-girl pair system, as it prevents her from piloting with Ichigo. She has a tumultuous partnership with Mitsuru due to their mutual dislike for each other. However, she cares deeply for her squadmates and will defend them. She is the first one of the squad to suffer from the accelerating aging process when her hair turns gray and her health weakens. She spends the next several years developing a cure to keep the aging of the other parasites under control. She and Naomi grow closer and begin a relationship. As an adult, she becomes a scientist and doctor.
Naomi - Hiro’s original partner before Zero Two. She left the squad after failing to synchronize with Hiro and encouraged Hiro to stay at Mistilteinn. She later disappeared following a klaxosaur attack. She is later revealed to be alive and she is kept in a cryogenic sleep within Dr. FRANXX‘s laboratory. After being freed, she rejoins her former team, and begins a relationship with Ikuno. As an adult, she becomes a scientist and doctor.
- In affinity sense, the number 13 represents the primary focus on building a secure foundation for the future.
- It tends to determine the way to accomplish something without relying on others to make its decisions. It expresses itself creatively to encourage acceptance or understanding of its goals but pursues its goals in a pragmatic manner. In some superstitions and other religions, 13 represents the circumstances and events of one’s life tend to relate to security and rebellion that manifests in the future.
- During the seige of Gran Crevasse in Episode 15, Squad 13 was part of the 6th Company. They fought alongside the 9's and Squad 26.
- It is hinted that Squad 13 was chosen to be an experimental unit by Dr. FRANXX because his former fiancée died during the 13th prototype FRANXX startup ritual.
- The squad was activated sometime in August following their graduation ceremony and it disbanded following the galactic battle with VIRM on May 10. The squad was active for approximately nine months.
- At the end of the manga, all ten members (with the exception of Naomi) survive the final battle against the Klaxosaurs (VIRM never invaded Earth as Papa was killed by 001 before he could initiate the invasion) and went on to live happy lives.