noun. in short a buddies girlfriend that is uncool, spiteful and on the verge of being overweight. The defining quality of a "beast whore" is when the "girl" while going out with your buddy, continually expands to the point of obesity, then dumps your buddy to gain more weight leaving your friend heartbroken.
John, don't let that Beast Whore get you down!! Go get a skinny chick!
by Dr Asseater August 02, 2006