Yoko Hayama, a mature woman with a voluptuous figure exuding adult charm, angers her stepson Yoshio over a trivial matter. She is violently fondled and photographed against her will. Using the photos as blackmail, Yoshio forces her into becoming his sex slave. Though she continues to act sweetly in front of her husband, she can no longer avoid the abuse. While her husband is away on business, she is repeatedly raped by Yoshio and his friends. Gradually, she begins to feel pleasure from the young men's bodies, slowly ceases resistance, and starts walking down a new path as a humiliated sex slave.