The man who lived with her was thinking about getting married. She also had a good relationship with her younger sister, Sachiko. One day, a sudden heavy rain caused the trains to stop, and her younger sister became stranded and came to her older sister's house nearby. However, she was stranded at work and became stranded, so she ended up alone with her step-sister , Sachiko. When he invited Sachiko in, she was soaking wet and her underwear was visible, and he felt her as a woman, which he normally doesn't feel, and he lost his reason and kissed her.