小門泰子 - 田舎から訪ねてくる義理の親。パート3

The mother of the wife and the had a physical relationship before. She thought the forbidden relationship that she couldn't tell anyone was just a one-time thing, but... she is alone with her mother-in-law who came to Tokyo again, and she remembers the mistake she made that night, and the immorality and elation that she can't forget, even if she doesn't want to!