This is just simple to define. It is the slick smelly substance created from farts, sweat, poop, and anal seepage. It stays tucked in between the butt cheeks in everyones crack. It can vary in amounts, and consistency; depending on how often one takes a bath or farts. The uses for this product are many, one is to help lube the large cracks of fat people as they walk. Another one would be to load a finger with the substance to annoy someone with a stinky finger or for self defense. Also see butt grease with snow flakes, dingle berries.
I smeared butt grease on my nephews nose to stop him from farting in peoples faces.