Holy Moly I want to go back and read the whole series adding in this book where it belongs! As always, I have been holding onto this book forever and finally pulled it out. 
 Obsession is about Hunter (sigh, Hunter), the Arum we were introduced to in the Lux series. At the time, of course, we were too wrapped up in the Luxen and this book may or may not have been overlooked. Believe me, I'm kicking myself for being one to actually do it. 
 I now have a completely different perspective on the Arum and everything they represent. We already knew Hunter was different than the others of his species since we saw him with Luc.(Yes, Luc is in this book as well!!) Now we actually have insight into how this species came to be and exactly how amazing the Arum, who we once thought were the only bad guys, truly are. 
 Thank you Jennifer Armentrout for giving me such a treasure. This book just proves exactly why I fell in love with your writing in the first place.