I first read this book like.... 6/7 years ago since then my rating went from 4 stars to 3. Let's see why: well, this book isn't for grown ups, we can all agree to that, but it can easily read from teens between 13 and... 16? The concept is great but it lacks in development and explanation in the story. What made me reconsider the rating were the lines though. So immature! Hahahaha but that's only because I read it as a 20 year old. Infact when I first read the book I was stunned, but still gave it 4 stars, mostly (knowing myself) because of lack of development of the plot and the powers described in the story. 
 Anyway, it is an enjoyable read!