Thongs provide less coverage than a panty and sacrifice the back portion of the panty in order to remove any visible lines that are created by the derriere seams of underpants.
The boy brief or boy short also eliminates the derriere seams of traditional panties, but can create awkward lines around the thighs; sometimes this result can make the legs look like stuffed sausages.
Some sexy versions of the body stocking are crotchless and have the derriere cut out of them.
First, the lack of coverage - less material covering the derriere must equate to a less comfortable panty, right?
Sexy booty shorts puts the emphasis squarely on the derriere and that makes them striking and sensual lingerie pieces.