One morning, mother Rie, on her way to the bathroom, notices her son Yoshio is already inside. She quickly tries to close the door, but grows suspicious when she sees him hunched over and opens it again. There, Yoshio is suffering with an intense morning erection, his cock rock-hard and preventing him from urinating. Desperate to use the bathroom herself, Rie hesitates only briefly before deciding to help her son relieve his condition.