A female whos private areas most likely reek a unsanitary odor. A typical fart butt will recycle under garmets and hamper dive her clothing repeatedly. This type of female is typically unattractive and over weight. If the severity of the girls clenliness and appearence is to the utmost extreme they can be redifined and graduated to a poop butt.
Thats girls thong was plastered to her ass, what a fart butt.
V. When you do a raspberry on someone's butt cheek.
N. A game of grabass where you run around and try to do raspberries on each other's butt cheeks. Best if played on a cold ocean shore.
Megan played Fart Butt last night and lost big time.