Hisayo helps with household chores at the Harada residence while her childhood friend Ikue is hospitalized. One morning, she goes to wake the younger son and sees his erect penis through his underwear. Having long gone without intimacy with her husband, Hisayo gives in to temptation. In doing so, she begins awakening to desire for other men. The reclusive eldest son and Ikue's husband each draw her in with their attractive appearances. As her relationships with these men deepen, Hisayo's heart gradually becomes stirred.