An erotic drama about the forbidden physical relationship between a wife whose husband is sickly and bedridden, and her father-in-law who supports his son and daughter-in-law. Since her husband fell ill, Azumi has been sexless, and her lower body is throbbing with heat. One day, as she peeks at her father-in-law getting changed, his erect penis catches her eye. At night, the wife indulges in masturbation, remembering her father-in-law's thing. Her father-in-law peeks at the act from the next room. Wanting to satisfy his daughter-in-law's feelings, the father-in-law forcibly opens the forbidden door. At first the daughter-in-law is confused, but gradually she becomes captivated by her father-in-law and begins to desire him herself, because it's forbidden.