Seiko is dissatisfied with her sex life with her husband. As if he could see through Seiko's feelings, her stepson Yoshio begins seducing her. Although she knows it's wrong, she submits to his orders and fulfills her own desires. Yoshio's demands escalate, and while her husband is away on a business trip, he invites many of his friends over and continues to rape Seiko. Before she knows it, she falls into the quagmire of carnal desire...
