A single mother named Yukari has raised her son Shuichi all by herself. However, due to her overprotectiveness, Shuichi has become spoiled and abusive towards his classmate Hajime. When Yukari finds out about this, she apologizes on behalf of Shuichi but her efforts are met with resistance from Hajime, who seeks revenge. He takes advantage of the situation by seducing Yukari physically. His thirst for vengeance doesn't end there; he even goes as far as propositioning Shuichi, asking him if he can borrow his mom for some time...