This arc frustrates me because in any other manga it would be a fantastic portrayal of demons. But it doesn't fit here. It's the opposite of the overall theme of the entire series, about Frieren's interactions with the other races that make her seem cold and alien but that are subtly still similar to them. Yet here there's the demons that are sociopaths and it's simply "no, no twist, they're just sociopaths". It feels contradictory for it to be played straight and it kept making me wait for a twist, not because I wanted a twist, but because it seemed like what made narrative sense. And not having leaves me saying "okay, what's the point?" not because I think it needs one instead of just being a neat adventure, but because it made me expect one.