Futa sans balls

futa_sans_balls is a tag on rule34.xxx, that displays anime girls with both a penis and a vagina. Sans means without, so futa_without_balls would be the English spelling. It originated from a call with Arthur and Jimeral, in which Jimeral is screensharing him on rule34.xxx finding weird fetish porn, eventually finding futa_sans_balls.

The joke was used mostly because it had sans in the name, a character from Undertale, and it is used by Jimeral and Arthur.