Two aging crooks are given two weeks to repay a debt to a woman named The American. They recruit their recently deceased partner's son to help them break into a laboratory and steal the vaccine against STBO, a sexually transmitted disease that is sweeping the country. It's spread by having sex without emotional involvement, and most of its victims are teenagers who make love out of curiosity rather than commitment.

Puberty Syndrome—a rumored, mysterious syndrome that only affects those in their puberty. For example, a bunny girl suddenly appeared in front of Sakuta Azusagawa. The bunny girl's real identity is Mai Sakurajima, a teenage celebrity who is currently an inactive high school senior. For some reason, her charming figure does not reflect in the eyes of others. In the course of revealing the mystery behind this phenomenon, Sakuta begins to explore his feelings towards Mai. Set in a city where the skies and seas shine, Sakuta unfolds the meaning behind his bizarre encounters on women with the said syndrome.

2019 anime film directed by Sōichi Masui

2021 film directed by Nobuhiro Doi