This is shaping up to be my favorite urban fantasy series. One of the reasons is the complex characters. Although the books tend to be upbeat in tone, there is an underlying darkness that appeals to me.
Rachel, the heroine, is a wonderfully kick-ass heroine, but she's human enough to be real. She makes mistakes, but she also learns from her mistakes. Additionally, the relationship between Rachel and her vampire roommate and Rachel and her human boyfriend really intrigue me. The personal dynamics make the book a fascinating read. I also love Jenks, Rachel's pixie companion. His swagger and ribald humor are wonderful.
The world, too, interests me. Its a cross between post-apocalyptic and modern day, and the mix is interesting. Harrison has done an excellent job of world building, making her setting so realistic that it almost seems as if it could happen.
Finally, I loved how this book built on the themes from the first book in the series. And since the story ended with a few cliffhangers, I'm looking forward to book three as well.