Mahiro has been married to her husband for several years, living with the man she's known since childhood and has always looked up to like an older brother. However, one day she receives news from her husband's family that his younger brother, Shiro, has been injured, and she is asked to provide care for one week. Mahiro has always felt uncomfortable under the gaze of her father-in-law and brother-in-law, as well as the oppressive atmosphere of her husband's family home. Still, she has no choice but to go. Yet this supposed caregiving arrangement is merely a pretext for them to do as they please with her. Her father-in-law slips drugs into the meals he serves, and soon Mahiro becomes an easy target in this rape-filled household, unable to resist.