Iori Yuki had known her boyfriend for a long time and it was time to bring him home to meet his family, but when his father was at work, only his mother was home. While looking for the bathroom, he accidentally Seeing his lover's mother changing clothes, his curiosity and lust made him stop and look for a long time. When her mother finished changing, he sneaked into the room and picked up the newly changed underwear, which was still warm on his body. She was masturbating. When he was discovered, he was scared, but unexpectedly, instead of scolding, his lover's mother was gentle because it had been a long time since she had had sex with a young man. After that, whatever happened happened, both of them had a secretly happy time without anyone knowing.