when you are fistingsomeone with diarhea. And you wait for all of the persons feces to build up, before removing your fist, and letting all the shit splurt everywhere.
Prior to butt sex you load your partners anal cavity with with Mentos. As you are penitrating your partner with your member, you pour soda in their anus and let nature take its course.
Kevin could no longer achieve orgasim unless his wife, Ralph performed vulcano anal on him.