It lost a star simply due to the molasses-slow story pacing.
The other <-.5> star was due to the slow plot that included a lot of character fleshing out and relationship building, both of which I absolutely loved. I was genuinely invested in the Anna/Ty/Cathy/Mel dynamic. To me, Kit seemed secondary and for once, we, as readers, aren't treated to secondary "best friend" characters who are there simply to bounce dialogue off.
Normally, I'm fairly involved in the romance angle, but this one to me was truly dominated by the strength of their friendship. Between Mel and Anna, and Mel and Cathy, I was completely stunned how easily and deeply I bought into their relationships.
At first, Cathy's descent into dating a vampire made her seem fickle, and air-headed. Simply said, I wasn't much of a fan. (I was wholeheartedly with Mel, it seems). Further into the story, when she defends the choices she's making with Francis and verbally demolishes Mel with just how passionately she feels about it, I found I liked her, and respected her much more than I had expected.
As a last note, the different angle of not having a human-vampire relationship spring up was fresh, and I enjoyed it.