User blog comment:IamJakuhoRaikoben/Chapter 353: Exorcism, Review./@comment-4933386-20130928023243/@comment-7418318-20130930104657

Those demons are pretty harmless, so maybe he only hunts bigger prey.

Maybe he didn'T believe the rumors about there being demons (other than the Fairy Tail members no one knew for sure after all).

Or maybe he doesn't specifically hunt down Demons, but just exterminates them if he happends to run across them.

Or maybe he is on a quest to only exterminate specific Demons.

Maybe he doesn't even have a problem with Demons as such and only attacked Atlas Flame for some other reason.

ect...

We know far to little about him to make a judgement on this question already.