Hiro (CODE:016) Appearance: A boy who looks quiet at first glance, with messy black hair and blue eyes. As the story progresses, small blue horns grow on his head. Personality: Sincere and cares deeply for his comrades. Once called a prodigy and a central figure among the children, he suffered through a period of deep conflict when he became unable to pilot a Franxx. Role: The protagonist of this work. A parasite for Strelizia. Possessing his own set of values, he becomes the catalyst for questioning the system of the "Papas" who manage their society.

Zero Two (CODE:002) Appearance: A beautiful girl characterized by long, vibrant pink hair, two red horns growing from her head, and red eyeliner around her eyes. Personality: Free-spirited and fearless. Possessing superhuman physical abilities, she initially showed a coldness that looked down on others, but she displays blind affection and strong obsession toward Hiro. Role: The heroine of this work. A special individual carrying Klaxosaur blood. By meeting Hiro, she integrates into Squad 13 and leads the front lines as an ace pilot.

Ichigo (CODE:015) Appearance: A petite girl whose trademark is short blue hair held back by a hairclip. Personality: Serious with a strong sense of responsibility, she is the picture-perfect honor student. She secretly harbors deep romantic feelings for her childhood friend Hiro, which sometimes lead to emotional outbursts. Role: The leader of the children in Squad 13. The pistil of Delphinium. She values the unity of the squad more than anyone else.

Goro (CODE:056) Appearance: A tall boy with an intellectual aura, wearing glasses and neatly parted hair. Personality: Extremely gentle and broad-minded, he possesses a mature temperament, always calmly watching over those around him. He has feelings for Ichigo but chooses to be a supportive figure, respecting her feelings for Hiro. Role: The sub-leader of Squad 13. As the stamen of Delphinium, he is the partner who supports Ichigo both mentally and technically.

Miku (CODE:390) Appearance: A cute, petite girl with a great figure and bright brown hair tied in twin tails. Personality: Hates to lose and is strong-willed—a so-called tsundere. While she can be foul-mouthed, she is actually very prone to loneliness and has a delicate side that fears seeing her comrades get hurt. Role: The pistil of Genista. Although she and her partner Zorome engage in daily bickering, they are essentially the most perfectly synchronized duo.

Zorome (CODE:666) Appearance: A boy with spiky brown hair and a somewhat cheeky facial expression. Personality: Confident and a show-off. He holds a strong admiration for the "Adults" who manage the city and possesses a naive belief in the system, fighting to be recognized by them. Role: The stamen of Genista. A troublemaker, but also the squad's mood maker.

Kokoro (CODE:556) Appearance: A beautiful girl resembling a holy mother, characterized by wavy flaxen hair and gentle, drooping eyes. Personality: Soft-spoken and full of compassion, yet very strong at her core. Triggered by an old book on "childbirth" she found by chance, she develops a strong interest in the mysteries of life and love with the opposite sex. Role: She serves as the pistil for Genista, paired with Futoshi in the first half of the story and Mitsuru in the second half. She plays a vital role symbolizing "human love and the connection of life."

Futoshi (CODE:214) Appearance: The only one among the children with a large, plump build. He has a kind face. Personality: Loves to eat and is a bit of a jokester. Extremely pure-hearted, he passionately loved his first partner, Kokoro, and lived to protect her. Role: The stamen of Chlorophytum. He experiences despair when his partnership with Kokoro is dissolved (partner shuffle), but he overcomes it to grow significantly both as a warrior and as a man.

Ikuno (CODE:196) Appearance: A cool, intellectual girl with black hair tied back and wearing glasses. Personality: A person of few words who rarely shows emotion, but hides strong passion and conflict within. She actually harbors romantic feelings for Ichigo that go beyond friendship. Role: The pistil of Chlorophytum. Later, to stop the rapid aging of the children's bodies, she shifts into a role supporting their future through the fields of medicine and science.

Mitsuru (CODE:326) Appearance: A boy who looks prideful, with neatly trimmed black hair (later shaved into a buzz cut). Personality: Initially cynical and distrustful of others, he held a strong obsession and hatred toward Hiro. However, by facing the limits of his own body and being touched by Kokoro's kindness, he learns of deep love, however awkwardly. Role: The stamen of Chlorophytum in the first half of the story and Genista in the second half. He forms a deep bond with Kokoro, becoming the one who most significantly challenges the Adults' managed society.