Mmm yes I can see why you don't want to butcher the main characters, how about a girl comes in wanting her sex removed? As a present for her boyfriend?
Also would be nice to have a girl and her boyfriend come in and she wants to be cut in half by guillotine just above her hips while having sex. But her bf has a hugely long cock like Eric and the blade cuts her body and his cock in half as he's cumming inside her?