Since her husband's solo business trip, she's been suffering from intense sexual frustration. Even though she masturbates daily, her loneliness only deepens. Her sighs grow more frequent with each passing day. Her son, Daisuke, is heartbroken by her state and contemplates what he can do to help. One day, he catches her masturbating. Witnessing her alluring act, Daisuke decides to comfort her with his body, embarking on a forbidden act of filial piety.