Diana Rowland's Mark of the Demon

I am currently reading Diana Rowland's first novel Mark of the Demon. It came out last year in 2009. I can highly recommend it. Good story and strong characterization. She writes very, very well and evenly. A joy to read. The main character is Kara Gillian a PD detective and summoner of demons. The demon world is developed in an interesting way. The higher the demon the harder it is for them to stay on the earth plane unless they are bound to a human in some way. Demon lords are not so willing to be either summoned or bound but can have an interest in using the earth's resources (including humans) for their own ends. The serial killer is not a side story but well-developed so there's balance to the human evil and the supernatural world. Supernatural is not equated with evil but rather with unilateral desire and thus indifference to earthly morals.