I found it easy to read and the plot was interesting. The sub-plot of realising she was falling in love with her best friend was an added bonus.
Never in a million years would I have guessed who the bad guy was, it was definitely a mystery trying to figure it out and the chapters from his POV were chilling at times. His lack of feeling for what he was about to do and the pleasure he got from getting the girls to trust him. *shivers*
As for Jay and Violet, they were likable though Violet was a bit blind when it came to Jay's feelings. I'm sorry, Vi, but it was obvious from early on that he cared about you in more than a friendly manner.