The quotes from other works at the head of each chapter was a nice touch. I recognized a few from reading those books (i.e. Dean Koontz).
By the end of the book, the creepies on my skin were sufficiently crawling. There was a moment when Charlotte asked "Who do you think that is?" and Zack replied, "No clue, and I don't want to find out." That's how I felt throughout the reading. Moments when I didn't want to continue, but couldn't stop reading because I needed to get through that section in all haste. Excellent!
The dialogue was exceptional, very believable and when the end arrived, I was very satisfied. It concluded nicely.
Overall, if you enjoy a good chill, this book won't disappoint. I'd never heard of this author prior to reading this, but I'm glad I discovered her.
Oh -- just one little thing -- please, please, please get a professional cover made. It does not, in any way, do justice to the writing.