Want to add a tag or pool for such images like this:favgroup #5024.
A view that shows both sides of the buttocks at the same time, but the crotch or any clothing is not exposed from the inside of the buttocks.
These are not all suspected no panties, but can also include confirmed no panties(post #2435754), wearing panties(post #3601668) or other clothing(post #2842581), even nude(post #3830472,post #3480581).
(Maybe ass_without_crotch or bare_ass ?, like crotch_invisible_through_ass)