Yui, a young married woman, struggles with emotional turmoil as her husband suffers from sexual dysfunction due to illness. Seeking comfort and intimacy through an affair, her life takes a complicated turn when she begins living with her brother-in-law. He harbors quiet, deep feelings for her, drawn to her vulnerability. As they share close quarters, Yui's emotions begin to shift, blurring the lines between forbidden desire and emotional connection. Themes include married woman, incest, titty fuck, sister, and cowgirl position.