Not to be confused with Swamp Ass, Sweat Ass occurs when someone forces a sweaty state of the ass. Similar to Swamp Ass, if not treated, Sweat Ass can lead to a more serious condition called duck butter.
Johnny was riding down the road when he noticed that Trent had turned on his heated leather seats. His ass was dripping with sweat. "Thanks for the sweat ass," he told Trent.
(n.) A grossly or overly hairy ass; an ass that is completely covered with hair, thus covering any skin and only showing the thick mat of hair grown on top; a hairy ass which causes excess sweating
This happens when someone sweats profusely from their ass and leaves their seat all wet so when the next person sits in it they get sweaty ass on them.
This person at our work sweats a lot and when I sat on their chair after they left my ass got all wet so now we call that chair the "Sweaty Ass Seat"