Haru happens to see Tsukimi, his classmate, masturbating at a sick-room. Though she notices him, she doesn't stop it..., and they have sex in the end.... At that moment, Yuki, a sick-room teacher, comes back and finds them sleeping together. Yuki thinks Haru raped Tsukimi, but Tsukimi defends him. According to Tsukimi, her family members are nymphomaniac. It can't be cured, and her symptom is getting worse. Following Yuki's proposal, Haru regularly has sex with Tsukimi. While that, Yuki looks for someone, who can cure it. And since then, other girls start to approach him. Tsukimi gets jealousy, and he receives a threat letter.... His sex life just starts now....

[From ErogeShop]