Burnt Offerings - Laurell K. Hamilton
And this is where the series lost me. All that work developing a character (a good one even!) just to throw it out the window for smut. I didn't even make it through the entire book, which is SO rare for me. If you're going to get it on, at least make the motivation both plausible for the character you created and tolerable for the audience you've amassed. By the looks of reviews later in the series, it only gets worse so I'll take my leave at #7.