Mio entered the family as his second wife and became Toshio's mother. - During his adolescence, Toshio did not accept Mio and his bad behavior became noticeable. - Mio wants to be Toshio's mother and acts devotedly, but Mio's body is too young, beautiful, and erotic to be called a mother. - Toshio's homeroom teacher demands his body in exchange for avoiding expulsion, and Toshio's friend secretly films the scene. - He uses the image as a material to press for a relationship. - Mio swallows her tears and decides to accept the despicable request...