when your pants are eaten by your ass and you can see your crack
"man that guys got a major ass monster."
by frosty8 July 10, 2008
A living creature that is born out of your asshole. It runs around and rips people's heads.
"My daughter got eaten by an ass monster!"
by Markey May 22, 2003
One who has a nice, big, sexy ass but has an ugly ass face.
Damn lookit that ass!! hope that ass monster doesn't turn around..
by peter January 23, 2004
a person with a monsterous ass that often develops nicknames such as "laffy taffy" or "ba dunk a dunk" and may cause dry eyes if looked at too often due to lack of blinking
"Damn girl, how you get all of that in them jeans, you assmonster!"
by Beth G. October 26, 2007