User blog comment:Kazekage21/Half Demon/Half Humans and Demonic Devil Fruits/@comment-3555397-20120111215507

Personally, I don't think that there should even be demons. if no demons were shown in OP then we shouldn't have it. I haven't complained about it yet because Brook has shown that he can harness the power of the underworld and if there's an underworld, I can only assume that there are demons.

I agree with a character having a demon aura because Zoro has one but demon form, I'd say no but that's just me :P

Other than that, I don't get your good vs. evil thing :P