From an early age, Masato grew up in a single-father household, and before he knew it, he developed a crush on his friend's mother, Yuri, almost like admiration. Masato was unable to talk to anyone about his feelings, so he finally consulted his girlfriend, the person he had a crush on. Yuri teaches him how to masturbate, saying, ``Don't tell anyone,'' as he has no knowledge of sex. Unable to suppress his reason due to his first pleasure, Masato pushes Yuri down. Her body, which had not been connected to her husband for a long time, reached climax over and over again due to his violent piston, which violently gouged the vaginal walls.