While this does make use of some of the same tropes and motifs found in too much Urban Fantasy today, it is a cut above. If you are thinking it will be like Carey's Kushiel books, think again. There is a hint at a romantic many sided figure, but just a hint, the main focus is a mystery. So while the heroine, Daisy, feels lust, she doesn't act on it.
So Daisy is a special girl because she is the offspring of a human mother and demon father. I have to say that as much I as enjoy Armstrong's Women of the Otherworld, Carey does a far, far better job than Armstrong in depicting the conflict of being a demon's daughter. This is particularly true in the closing pages of the novel.
I do have to wonder though, has it now become a rule that every urban fantasy novel, but the Kitty Norville books, involving a heroine have a vampire/woman/werewolf love triangle? Granted, here it is a ghoul, but considering that ghouls fed off of emotions, they are still kinda vampire. And since it seems to be the werewolf that will most likely win, I have to wonder why because he had more chemistry with Daisy's BBF, Jen.
But that is the great thing about this book. It's almost the anti-Anita Blake. Not only does Daisy respect the men she works with, who also respect her (because they are all professional), she gets along very well with most of the women in the book. She is very close friends with Jen, and it is a good friendship. She gets along well with her mother, and her fairy godmother (who isn't a fairy and isn't really her godmother, but still). In many ways, while Daisy is the only woman on the local police force (or at least the only woman who investigates), she would not have been able to solve the mystery if she hadn't known she could go to the other women for help.
And Hel is awesome.