A year has passed since her only son Takashi died, and Yumi, his mother, has not been able to organize his room. Today is the anniversary of his death... She gathers up the courage to enter Takashi's room and finds many erotic books and DVDs. Although she is confused, she can't help but feel horny and indulges in masturbation. Furthermore, when she senses that someone is watching her, her body suddenly becomes unable to move. "Could this be sleep paralysis...?" What is the true identity of the mysterious presence approaching the confused Yumi?