If someone loves the tongue on anus action, you would refer to them as a mad bowel growler.
When one extends cunnilingus from port 1 to port 2, they are bringing the bowel growl into play.
Hey, Frank, that chick at the bar looks like she'd love a good bowel growl
She's nuts for the bowel growl
With the economy the way it is, always remember, bowel growls are free