A twifuck is a term that refers to the obsessed bitches that cant stop talking about twilight. Despite the fact that the book lacks any real character development or definition.
when a guy lays down and a girls sits on him (letting him eat her out) while another girl is sucking his dick but her legs are on the girls shoulders (the one letting him eat her out) and the girl sitting on the guy is eating out the girl sucking his dick.thus, making a triangle