A married couple, Chikage and Saburo, live in a majestic mansion adorned with blooming plum blossoms. Saburo's younger brother, Masaharu, also resides with them, and the story unfolds around their daily lives. Chikage appears refined and demure on the surface, but in reality harbors a bold and uninhibited side when it comes to sex. Drawn in by her seductive and provocative demeanor, Masaharu grows increasingly infatuated with his sister-in-law, gradually becoming obsessed with her allure. The film depicts how the complex relationship between the three evolves.