INITIAL THOUGHTS: 
 Pure is one of those rare second books in the series that actually rivals the greatness of the first book. This book wasn't stagnant, or the same as Half Blood. It was completely different and did a fantastic job of advancing the plot, presenting a whole different set of problems for the main character. Pacing is moderate to fast. The romance is changed up, moving away from Aiden and Alex and focusing more on the newly developing relationship between Alex and her Apollyan counterpart Seth. I guess you could say this has a slight variation of the typical love triangle we see so often in YA literature. 
 The last ten percent of the book is extreme, action packed, with some pretty intense fight scenes. The ending produces some closure, but is open-ended. Its not a nasty cliffhanger. Its pretty obvious there still is a significant amount of story left untold. This book tees up book three quite nicely. I have a strong desire to pick up the next one and keep reading. How about you?