An act performed during sexual intercourse where a person will place their penis on the edge of the anus and cum, forcing the cum into the anal cavity without penis insertion.
X doesn’t enjoy anal but is okay with Grease Gunning. Y Grease Gunned X’s ass as a release instead.
When a ugly chick with a fat ass is walking and the curds are bubbling out and the rolls are waving back and forth like "two hogs fighting in a gunnysack".
Damn dude! Check out that ass... it is like two hogs fighting in a gunnysack.