Assless pants, I think. Nudity allows too many viewing options, so you want JUST the ass to be naked.
I guess if you’re less creative, you could put stickers or writing/embossing on the seat of the pants. They do sell pants with writing on the ass.
Yo, Butt Out, man.
Okay, I did and my darling Marcie said that was too much to ask of any pair of pants.