The husband is deeply in love with his beautiful wife Reiko, who has remained as beautiful as ever since they first met, but perhaps due to his age, he has recently been having trouble getting an erection. If this continues, Reiko will lose interest in him. Worried, the husband finally turns to medicine. Unfortunately, Reiko and her son accidentally drink an aphrodisiac-laced drink... Even though the room is not even hot, her body is sweating and her uterus is beginning to ache. In the heat of the moment, mother and son impulsively open the forbidden door...