"Eriko" is an ordinary housewife who lives in peace with her husband, daughter, and son-in-law Hiroaki. Calm everyday is a treasure of Eriko. One day, Eriko has an affair with a young man who is a part-timer, and Hiroaki witnesses it. Hiroaki was stimulated by the appearance of Eriko who pleaded to keep it secret, and grabbed Eriko's huge breasts. The two drowned in forbidden pleasures.
