Karin, who works as a nurse at a certain hospital. One day, her ex-boyfriend, who was too much of a scumbag, was hospitalized, and to her dismay, Karin was assigned to take care of him. The scumbag, who still has a strong sex drive, shows off his erect dick and demands sexual assistance. Despite being engaged, Karin can't forget the dick she had tasted so much in the past, and she ends up accepting it without thinking. From that day on, a rotten hospital sex life began.