I have read few chapters of Frieren but it's really because the demons in her world operate on different rules, and do not feel empathy. Like Goblin Slayer's goblins, but even more dangerous since they don't look like obvious monsters. The rest could be normal anime girls with a horned headband (aside from Nezuko who's had 1 or 2 bloodlust moments but who ultimately tries to resist it)

Watching the anime, I'm kinda bummed down that it's confirmed immediately.

Goblin slayer is shown killing goblin children in the first chapter, you're left wondering for a while, until the goblin lord reveals that his whole career relies on human empathy.