A pool analogous to the はいてない？ tag/concept on Pixiv. This is for images where it's very likely that the character isn't wearing panties, but you can't tell for 100% sure. Of course, this only works when she is wearing an outfit you'd normally expect someone to wear panties with, such as a schoolgirl uniform.
Since this is somewhat subjective, please use discretion when adding things to this pool. Don't add things to this pool JUST because they're tagged はいてない？ on Pixiv, use your own judgement.