Mitsuru

Mitsuru (ミツル) is one of the main characters in DARLING in the FRANXX series. He's a Parasite with codename "326" of Thirteenth Plantation, where he's partnered in boy-girl pair with Ikuno to pilot a FRANXX called Chlorophytum.

Appearance
Mitsuru is a very clean and proper student with sharp features. He has slicked back brown hair and piercing deep green eyes.

Personality
Mitsuru is full of pride and a strong cynical personality. He finds Hiro a rival. He hates being pitied and Kokoro cites that he never liked leaning on others for support.

EPISODE 1: Alone and Lonesome!
One of the orphans of the Garden, he was raised along with the others and watched as Hiro slowly lost his ability to pilot.

EPISODE 2: What it Means to Connect!
He is normally quiet and visibly annoyed at Zorome hitting on Zero Two.

EPISODE 3: Fighting Puppet!
He and his partner had trouble getting Chlorophytum to move and so he volunteered to ride with Zero Two in an effort to contribute while showing up Hiro. He proposes 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 and her stamen (Mitsuru).

The result leads to a deactivated Strelizia. 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 4: Flap Flap!
Misturu is in the infirmary, unsettled from his near-death experience of riding with Zero Two. He is called back into battle with Ikuno later in the episode in order to fight, with the two managing to connect this time.

EPISODE 5: 

He's shown to still be suffering from his previous ride with Zero Two, but tries to hide it until Kokoro finds him.

Hiro
In the past, Mitsuru seemed to have admired Hiro and his ability, citing that they thought he would be the one to lead them and thought strongly of Hiro as a rival. However, as the years went by and his abilities decrease, Hiro's image in his eyes deteriorated to the point where he found himself unable to stand the sight of it.

In Episode 03, when Delphinium, Argentea and Genista are in need of assistance fighting klaxosaurs, he suggests that he go with Zero Two to go save the others, as he was the only 'stamen parasite' there, and because he believed he could pilot it because Hiro did. After successfully connecting Strelizia and piloting it, Mitsuru boasted about how he could pilot it without fainting, unlike Hiro, and tried to take over as her official partner until he gets injured and passes out by the end of their mission.

Zorome
The two seem to share similar attributes, such as looking down on Hiro, but Mitsuru is more often than naught winding Zorome up.

Zero Two
In the aftermath of Episode 3, 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 prospective she tried to 'devour his body, blood, and soul'. And while she was doing it, she was smiling.

Ikuno
Mitsuru doesn't seem to have the same affinity with her as his partner that the others do with their counterparts. He blames her for their connection failing in Episode 3, telling her not to even bother when they couldn't get Cholorophytum to function and then attempting to trade up to Strelizia with Zero Two without regards for her feeling.

Etymology
Mitsuru's nickname may use some of the numeral's readings from his real name "Code:326": mi from 3, tsu from 2 (ツー) and ru from 6.