One day, when my mother (Yumi) returns from work, her son (Tatsuya), who only plays games and does not clean up, gets tired and takes a nap on the sofa to take a rest. Tatsuya who is hungry shakes to wake up her mother, but she never wakes up. However, in front of the too defenseless plump body, Tatsuya's desire ignites and she begins to caress her mother's body.