The act of climbing the outside of the dividing wall of a public toilet and dropping a duece on an unsuspecting person who is also defocating. This can be dangerous and should be performed with a spotter to avoid injury and should also involve a hasty escape route.
see also Hot Carl Bomb
Garreth was walking through the airport when suddenly his legs cramped and lost all strength. He knew what was coming and it wouldn't be pretty. He hastened to the lavatory, quickly laid down the paper seat, and dropped his trousers. Before he actually made contact with the paper-protected plastic, liquid hot magma sprayed the back of the bowl. As his quivering hamstrings regained their control, Garreth felt relieved and reached for the toilet paper to begin his ascent from the public bowl, and thats when he saw it; a white pimply ass perched over the top of the stall. In pre-wiped frozen horror, he watched as the intruding ass released 12 inches of unholy fecal rope that splatted down onto his right knee. Damn it! If not for the pre-diarrhea leg cramp weakness, he would have been able to avoid this sky shit. On top of everything else, cleaning up his soiled leg took too much time and Garreth missed his connecting flight.