After her son-in-law Shinji's company goes bankrupt, Maki Tomoda and her husband return to her parents' home while he searches for a new job. One night, Shinji confesses that they've been in a sexless marriage, and Maki honestly admits she feels the same way. Unconsciously drawn to her mature allure and voluptuous figure, Shinji's pent-up desire suddenly erupts and he aggressively makes a move on her. Maki responds sensitively to his forceful advances, trembling with pleasure as she craves more. The intense passion and tension between them marks the beginning of a new, forbidden relationship.