La soirée a mal tourné, très mal

What kind of a fucked up family is that? Just follow this story exposing what they do for fun, and you'll understand. The guy and his stepmother are thinking hard: they gotta give the stepfather a birthday surprise gift. Well, here's what they come up with. They blindfold him, bring him the guy's girlfriend whom he adores, and the three have steamy threesome sex! This is some hard stuff to handle, and the boyfriend watches the madness for a while, and then rushes out... We don't know about other people, but he could definitely use one.