This is the cause of sitting on a school bus on a hot day. The bus's hot plastic/rubber seats heat up against your butt causing the sitter to constantly shift. This constant shifting ends up with the sitters ass sweating causing a wedgie that is severly hard to de-wedge. This is known as Hot Bus Wedgie.
1 gets off bus
1: aw damn I got a bad case of the Hot Bus Wedgie.
2: HAHAHHAHAHAHA good luck de-wedging that!