After losing her husband, Nana Mi Kawakami raised her daughter alone. The daughter grew up and got married, then moved in with her mother, leading to an ordinary, peaceful life. But one night, everything changed when she secretly spied on her daughter and son-in-law in their private room. Shocked, she witnessed the gentle son-in-law vigorously thrusting into her daughter, making her climax repeatedly. The sight triggered long-buried memories of her own past as a sex-addicted creampie slut. Unable to suppress her reawakened desires, her lust soon spiraled into an uncontrollable craving for more.