Ai

 is a character in DARLING in the FRANXX. She is the daughter of Kokoro and Mitsuru and the first child to be born to parasites.

Appearance
Ai greatly resembles her parents. As a toddler, she has long blond hair, the same color as her mother's, and small pigtails at the top of her head. Her bangs are round like Mitsuru's and she has the same eye color as him, though they are the same shape as her mother's.

Personality
She seems to have inherited traits of her mother’s personality. She is a very cheerful and precocious child.

Episode 17
Kokoro, who had been growing curious of pregnancy and childbirth after reading a baby book, made a sudden pass at Mitsuru, who was confused and rebuffed her. The Nines later berated her for her desire to have a child in case she dies in battle. Mitsuru comforted Kokoro and they ended up sleeping together, unknowingly resulting in her pregnancy.

Episode 22
After suffering from morning sickness, Kokoro is told she is pregnant. She and Mitsuru are shocked and both are troubled with the indecision on what they should do. In the next episode, Mitsuru tells her his newfound reason to live is to protect her and the baby.

Episode 24
After deciding to have the baby, Kokoro’s pregnancy is monitored and she later gives birth to their daughter Ai. Mitsuru is overcome with love for his daughter when he first sees her and she holds his finger, bringing him to tears. Growing up, Ai is loved dearly by her parents, especially her father.

While playing in the field, Ai looks at Zero Two’s statue and begins saying “Darling”. Kokoro and Mitsuru hear this and alert everyone. They all join hands to send their thoughts to Hiro and Zero Two while the two fight the VIRM. Mitsuru says he chose the name Ai because he wanted it to be symbolic to Hiro and Zero Two’s bond. After Hiro and Zero Two sacrifice themselves to destroy the VIRM, Ai comforts her mother who cries.

Kokoro
Ai’s mother. Although initially undecided on what to do after learning her pregnancy, Kokoro gradually comes to love her child and is happy when Ai is born. Kokoro loves her daughter very much and often carries her around.

Mitsuru
Ai’s father. Upon learning of Kokoro’s pregnancy, Mitsuru becomes protective of her and supports her. When Ai is born, Mitsuru cries out of joy. He loves his daughter very much and dotes on her.

Etymology
Ai was named by her parents for "love" (愛). They wanted her to inherit the bond that both Zero Two and Hiro felt for each other.

Quotes
"Huh? Darling, daarling! Papa, 'darling!'"

- Episode 24