His wife's sister's daughter has gone to college, so her uncle is letting her stay at his house. Since he doesn't have any children of his own, he's not used to young girls' bodies, and this is a problem for his uncle. However, the girl secretly gets pocket money from her brother, and so that no one will find out, she passionately kisses and fucks a man more than twice her age. Her uncle notices this and is confused, but he's not going to be outdone, so he passionately enjoys the young body and lips, and the girl responds to it and feels great.