Someone who is being either annoying, inappropriate, or an asshole.
Suck vage, you're being a buttmonster.
An alternate name for a demon (or "pinky demon") in ID Software's original Doom game series.
Blood and viscera flew everywhere when I attacked the group of butt monsters with my chainsaw.
An oversized 'butt plug'. See 'Butt Plug'
You, me, the Butt Monster. Saturday night. Be prepared
somone who loves it in the butt.
David: "Chris.......no matter what, you always seem to have sex with that chick in the butt."
Chris: "I know dude, that's why we call her the butt monster!