User blog comment:IamJakuhoRaikoben/Chapter 361: The Two Bombs, Review./@comment-5668006-20131123040415/@comment-24066070-20131123100013

Why wouldn't he be a demon?

Tempesta had wind "magic" and the posion curse. Jackal can create explosions everywhere and has a curse to turn everyone who touches him into a bomb. So Silver may have his Ice Devil Slayer magic and an additional curse