Yusuke, who graduated from a university in Tokyo and got a job in the city, went on a two-night, three-day hot spring trip with his parents to fulfill his filial piety. Yusuke, who had been aware of his girlfriend's mother, Yurie, as a woman since he was a child, could no longer control his feelings for her, and without her father's notice, he forcibly had sex with her. Yusuke's heart is wavering between a sense of accomplishment and guilt...he knows it's not a good thing.