Oh, how vivid the imagination can be. It can literally create anything, even an anti-cellphone PSA whereby a man in a movie theater stabs a cellphone-using woman in the neck and then, seconds later, he f*cks the open wound he just created. I don't even know if what he did actually constitutes skull-f*cking. Maybe that move is like a skull-f*ckers version of the reverse cowgirl? Who knows?
I must warn -- in the event you didn't read the first few sentences -- this video is sort of graphic.