This is very similar to the ball busting fantasies that can be seen in the ball busting forum but i figured i would bring it here. All you have to do is write a perfect situation for your face sitting.

I would love a man and woman who recently got married not knowing eachothers fetishes. So the man does not know that his wife wants to grind his head into the ground and is about to get a painful surprize. Needless to say its against his will, she loves a man who will fight back