Faeries are even better than vampires. Firstly, you can actually make a deal with faeries and compel them to honour the deal. Secondly, that makes them even more deadly, because they're usually clever enough to twist the deal so it ends up harming you anyway. Just as Jim Butcher can't claim credit for vampires, he can't claim credit for faeries, but he sure can claim credit for the characters he creates to personify each…