Forced by his wife to abstain from sex for a month due to pregnancy preparation, Jinshi struggles to endure. After two weeks, he can no longer resist and resorts to masturbation for brief relief. His sister-in-law, Tsubasa, catches him in the act and becomes intrigued by his state of sexual deprivation, teasing and provoking him. Tsubasa herself has been suffering from a sexless marriage and growing frustration, which makes her increasingly aroused by Jinshi's situation. Despite trying to maintain self-control, he ultimately succumbs to her advances just as the day for his scheduled intercourse with his wife arrives. On that very day, Tsubasa appears again, leading to an unexpected turn of events.