Yayoi (Ko Uzuki) is a housewife married for two years, living with her husband and his younger brother. Her husband works constantly, while the brother-in-law remains unemployed, shut away at home. The younger brother becomes obsessed with adult videos, gradually mimicking their content in his behavior. Yayoi notices his disturbing changes but feels powerless to act, caught between confronting him and fearing her husband's reaction. As the brother-in-law's actions grow increasingly aggressive, he begins assaulting her. The darkness lurking within her everyday life slowly consumes her.