Wife Ayumi's relationship with her husband has grown distant and awkward. Lately, she finds herself barely speaking to anyone except her brother-in-law, Shunsuke, as she endures a monotonous daily life. However, Shunsuke is secretly struggling with gambling debts and sees Ayumi's dissatisfaction as an opportunity to get closer. On the eve of their tenth wedding anniversary, Ayumi succumbs to Shunsuke's seduction and goes to him. Overcome with guilt, she allows Shunsuke to take control of her body, as he becomes completely consumed by fulfilling his own desires.