Abby

Abby is an edgy bounty hunter that appears near the end of the game in Hell as a boss. Her design is based on an original character from Abbock, one of the game's testers.

She can be recruited in the sewers if you've encountered more than 30 abominations. If you talk to her in the sewers but don't let her join, the fight against her in Hell will have a 2nd phase.

Her quirk in battle is being super effective against demons and monsters while just being overpowered in general.

The game itself describes her as:

"37 inches of pure edge. Also talks like a Twitch user."