On his way to work, Shigeru accidentally encounters a woman who is lost and guides her. When he returns home after work, he finds the woman in his house. "A friend is coming to stay," his mother says, introducing him to her classmate, Sumika. Despite being his mother's classmate, Sumika has an unbelievable beauty, causing Shigeru's heart to race... Unable to sleep due to excitement, Shigeru leaves his room and accidentally sees Sumika pleasuring herself. Aroused by her secretive lewd behavior, he impulsively pushes her down...
