Saying the phrase is redundant, like saying "fingerless mittens" because chaps, by design, have no ass (or crotch, for that matter). Luckily they have hot guys willing to jerk off in them.
This little hottie is going to fit in perfectly at the Black Party this weekend in New York. For those who don't know, it's a circuit party-esque event where nearly everyone wears leather (and some where nothing at all) where "strange erotic acts" take place on stage into the wee hours of the morning. There is always plenty of public sucking and fucking, often with asses hanging out of chaps. See, that's the grammatically responsible way to express such an occurrence. We just don't want to hear you sounding like an idiot, or, even worse, wearing a pair of chaps that have an ass.
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· Young Leather Chaps Gloves Wank (xtube.com)