They all have to fuck the nymphomaniac niece
A girl who has wanted to feel extreme pain for a long time and along the way has discovered that she also gets pleasure from it, is a problem for any family. At least she doesn’t want to get pregnant, that makes it easier to cope. And it is when the older people decide that they have to solve the problem as it was done in the old days. And together he has to fuck the nymphomaniac niece because there is no other way to keep her pleased. Including double penetration, which is what she likes the most and is how she has orgasms the most.