Its when you are fucking a chick doggy style and you pull out your dick right before you are going to cum, place it on the top of her ass crack, then run a line of gunk from the top of her ass to her clit just like a caulking gun. This of course would also apply to the upper lip, forehead, ear-to-ear across the eyes, ect.

A casual invitation / threat used by an individual that is not afraid of fucking someone up.