One of, if not the, oldest styles of panties, covering the navel down but with minimal leg coverage (contrasting with their bloomer and girdle derived rivals that covered a significant portion of the leg).

Trigger: be_br_p, panties
Support: crotch seam, [color] waistband (these are existing tags)
Negative: lowleg panties, bow panties (you always need these for Illustrious and Pony panties), realistic, photo (medium) (shouldn't be needed, but listed in case)
Do NOT Use: Briefs (Illustrious knows this, but as the male underwear)

I was able to avoid uploading images for training this one (which is now prohibited) by using the reuse dataset option in the trainer.