Azusa's son, Koichi, is a sexual monster who only thinks about ejaculating if he has the time. He is troubled by his son who sees even his mother as a sexual object when he loses his rationality, but he suddenly remembers his mother's friend Mary Tachibana, a slut, and consults her about his son. A sexual monster battle between Koichi, who has an inexhaustible sexual desire, and Mary, who is willing to pay for sexual treatment, begins now.