Asahi Mizuno was born a girl, but was raised as a boy due to her parents' educational policy. Her girlhood is a secret that must not be revealed to anyone. Then, a bully finds out that she is a girl. He demands her body as a condition for not telling him his secret, and she loses her virginity. She becomes the plaything of all the boys in school, but contrary to Kokoro, her body begins to feel the joys of being a woman, and she loses control...