Excellent world building. Fun characters and a plot convoluted enough to keep any reader of Urban Fantasy interested. Spencer's a hero with all the issues you'd expect from any UF hero, but he spends maybe 10% of the book brooding over it, 90% of the time it's all action and getting shit done.
It's so good to finally have a slash UF that's plot focused rather than romance focused. And the uh, age diff between Main Character and Love Interest didn't hurt either.