While Yuuta is away on a trip, Tomoki, a shut-in living with his brother's family, is lured out of his room by Keiko and Hiyo, who use sexual temptation to "cure" his isolation. The forbidden encounters escalate when Tomoki's former student, Kozue, arrives and joins the group in their hedonistic activities. As the boundaries of family and propriety vanish, the house becomes a site of unchecked desire, culminating in a precarious situation as Yuuta returns home unexpectedly.