The Demon's Lexicon The Demon's Lexicon Trilogy, Book 1.

Nick and his brother, Alan, have spent their lives on the run from magic. Their father was murdered, and their mother was driven mad by magicians and the demons who give them power. The magicians are hunting the Ryves family for a charm that Nick's mother stole -- a charm that keeps her alive -- and they want it badly enough to kill again. Danger draws even closer when a brother and sister come to the Ryves family for help. The boy wears a demon'...