@Flare77 He was conflicted about it. Which makes him not unredeemable, I guess, except that since he's dead it's kind of too late. But it also means he knew damn well he was doing wrong. When you say "I'll do whatever dirty work it takes" you know the work is dirty. Seems to me to a fair extent he was just taking out his pain on the city, doing this self-indulgent "The love of my life is gone so nothing matters any more, it doesn't matter what terrible things I do"--dude, it matters to the people you do those things to.
Plus I don't know if anyone noticed, but he found out his crush was mass murdering people from his clan and
didn't tell anyone. Or do anything about it. Really, WTF?! Normally when you find out your main squeeze is a serial killer, you kind of do a re-evaluation. He seemed willing to just keep on seeing her while she slaughtered more people, until he was confronted with "Clean up the mess or die".
As to her . . . she's cursed.
On her own, she'd have just been amoral. She didn't care about human life except for people she actually knew and liked personally--deeply individualistic with no ethical code, although potentially very loyal to those few people she had a personal bond with. She was a wild animal that talked. But on her own she wouldn't have been going around killing people. She just didn't resist when the curse pushed her to do stuff, because she didn't care. But she could have led a fairly blameless life if it weren't for the curse.