What is Butterfuck?
1.
A really girthy woman whom you enjoy screwing.
Damn, that chubby chick? That's a good butterfuck!
2.
Idiot; Stupid person; roughly equivalent to "knucklehead"; derived from "buttfuck";
"Put down the cell phone and drive, you butterfuck!"
See
3.
to fuck somebody ugly in the ass with a stick of butter
dude im so drunk i'd butterfuck that fat dyke.
See