Mion is a female teacher who is in a slump in her relationship with her boyfriend. During a home visit, she is excited by the strong body of the student's father and indulges in carnal desires with him. The student witnesses this lewd behavior. Later, Mion is threatened and follows obscene orders. Gradually, her shame turns to excitement as she devours the student's penis. Mion's desires are exposed in this forbidden relationship. Her boyfriend is also excited by this. They confirm their love for each other by revealing their twisted sexual desires.