Wife Yuzu lives with her husband's father at his family home. Outwardly quiet and gentle, she secretly harbors a deep obsession with her anus. Unfulfilled by sex with her husband, she indulges in anal masturbation from morning onwards—unaware that her stepfather is watching. When he confronts her about her sexual frustration, he begins an intense anal training regimen. In the kitchen, he inserts foreign objects; in the bathroom, he administers massive enemas; in the living room, he takes her anally. Finally, he cums deep inside her repeatedly, completing the ultimate in-house anal NTR.