The tag implication #57494 diaper_only -> pantsless has been rejected.

Reason: Diaper_only implies no pants, which fits under the criteria for pantsless (diaper implicates underwear). It also already implicates topless.

EDIT: The tag implication diaper_only -> pantsless (forum #394599) has been rejected by @dragomess99.

The diaper-underwear argument aside, pantsless requires topwear and if you're only wearing a diaper there's no topwear:

When a character is shown wearing "normal" topwear, such as a shirt, jacket, hoodie or sweater, but is only wearing underwear, such as panties, thong or a jockstrap, or swimwear, such as a bikini bottom.

a character only wearing underwear should not be tagged as pantsless (even if wearing an undershirt with their underpants or panties), use underwear only

a character that is topless should never be tagged as pantsless