I.B.S. stands for Itchy Ball Syndrome. Applying to most males, when sweat forms inbetween the crevices of your ballsack and inner thigh. To releive yourself from this horrid disease a simple pinching motion to get your balls away from your leg is used.
Identified Butt Snatcher: The close cousin of the UFO's. The aliens that drive the IBS have been identified and scientifically classified. Instead of probing the ass, they simply probe it with their own "Tool".