>>93672 (OP)
It's just a neatly-designed memorable character that stands out (despite the claims to the contrary), especially among modern western adult cartoons. An obvious (and successful) attempt at furbait , she nonetheless steals the scenes she is in. Or so I heard. Haven't watched a single episode and, discussing the character with other enjoyers, it is not uncommon fur them to not even be interested in the show. Case in point, >>93684 !
The tumblerina outfit and haircut can be excused by the setting (literal hell) and when you account fur that even the piercings are on the modest side; been noticing far too many of those on drawings of other characters by western artists, guess it's the norm these days?
Also, >implying goth girls ever went out of style
Personality-wise, she looks malleable enough to either become a dommy-mommy, an i-can-fix-her pet project, or a soft nerd hiding under a jerk's mask, depending on whichever you fancy. Surely this has been expanded upon in the seasons that followed but who cares about canon if the show is apparently meh anyway.
Lastly, there is a feedback loop of artists drawing characters that are popular among the other artists they follow, and when HB debuted her character also inherited HH's momentum.