The Demon's Lexicon
Sarah Rees Brennan
 The story follows two brothers with a sordid past, Nick and Alan Ryves, who fight demons and monsters. They are on the run from a magician, from whom their mother supposedly stole an amulet, when they meet Mae and Jamie, troubled teenagers who come to them for help. Throughout the book they face horror, evil, and people who just generally want to kill them, while in the meantime, long kept secrets are threatening to unravel. In the lore of the book, humans can either be born with magical powers, or can make pacts with demons who will grant them power or use their own magic. Very early on, Mae expresses the thought that she may have once had magical powers, but that they went away. Nick chastises her for this, saying that if you have magical powers, they never leave you.