Six months have passed since the death of her mother-in-law, and Ririka has gradually grown accustomed to living alone with her husband. One day, her brother-in-law, Fumita, suddenly returns home. A constant womanizer, Fumita has always flirted with Ririka and repeatedly tried to seduce her. Though she's long been annoyed by his persistent advances, she eventually gives in to his relentless pursuit and ends up sleeping with him. Unlike her husband, his sensual and skillful touch awakens sensations she's never experienced before, driving her to repeated orgasms. Captivated by this newfound pleasure, Ririka continues to fall deeper into Fumita's obsessive seduction.