I'm a bit of a sucker for books based off movies I've seen, and after watching Jennifer's Body and adoring it, I jumped at the chance to read the book.
It was ok. Not amazing, not great, but ok. It was nice to get to read and visualize some details that weren't in the theatrical version of the movie (the funeral for example) and to get a bit deeper into Needy's mind. I particularly liked Needy's description of the fire, seeing as you only get to view it in the film version rather than hear a detailed description.
However, there were far more cons than pros. To me, Chip is an important character in the film, while in the book he seems like a minor character that almost wouldn't have been included were it not for the pool scene. The book itself also read much more like a novel for middle schoolers than something based off an R rated movie. In my opinion, the novel should have remained explicit, and should have been more detailed. I found it easy to visualize things in detail as I read only because I had watched the movie four months prior. While the gore is included, it's not written very well.
Another important factor is that while the film is primarily Needy-centric, there are scenes were Jennifer and Chip are the main focus, and we needed to see that in the book. Switching POVs would have been better than just Needy retelling the tale.
I might have given this novel four stars if there had been one more chapter detailing the events revealed in the credits of the film. I would really have liked to read Needy's point of view on that, but alas, it's not to be. All in all, a good read if the idea of a high school cheerleader eating boys appeals to you, but you don't want any explicit material or particularly gory details.