During my wife's pregnancy, I was even forbidden to masturbate, so I ended up having sex with my stepmother, Mika, who had come to Tokyo, and repeatedly impregnated her... Mika Sumikawa

The movie revolves around a complex family dynamic where the narrator, a husband, is forbidden from masturbating during his wife's pregnancy and ends up having an affair with his stepmother, Mika. The story explores themes of marital relationships, infidelity, and the challenges of pregnancy, highlighting the tension and emotional struggles within the family. As the wife's pregnancy advances, the household becomes increasingly strained, leading to a deeper exploration of the characters' emotions and actions.