Several years after the death of her husband, Yukiko has been living peacefully with her daughter and son-in-law, Shu. However, one day, Shu discovers Yukiko masturbating, and the family's delicate balance begins to unravel. Drawn to her, Shu becomes consumed by desire after witnessing her intimate act. Overwhelmed by these emotions, Yukiko struggles with growing inner conflict as her body and heart are pulled in conflicting directions. As the bonds of family begin to fracture, how will she face the consequences of their forbidden attraction?