Eight years into her marriage, housewife Keiko lives a content life with her husband, who is a bit unreliable but kind, leaving her with no real complaints. Yet, she quietly carries a lingering sense of emptiness. One day, she receives a sudden call from her former lover, who invites her to be a trial client for a new business venture—esthetic massage. Initially hesitant and embarrassed, she's strongly persuaded and eventually agrees to keep the appointment. But this single step becomes the turning point of her life. Once lured into a secluded room, she faces unimaginable humiliation and terror...