Yoshiyuki, who missed the last train and stayed at his friend's house, was captivated by the beauty of his friend's mother, Kumi. Late at night, he heard Kumi moaning from the quiet room and went to peek in. He witnessed Kumi masturbating and took a picture of it. Later, when Yoshiyuki visited Kumi's house, he showed her the picture and tried to get her to have a physical relationship with him.