*If you are looking for a book about assassins/ninjas this is not it! If you enjoy a more psychological kind of book then this is definitely for you*Ok, so this book had a few issues. Like why didn't Nix ever think about his parents? Even after he met Claire, he never once thought about them. Yeah, he finds out who his mom is and why he was there, but the point is he NEVER once questioned anyone about his parents, and his dad is still a mystery. Then there's Claire's and Nix's connection. I get why they felt slightly connected and their kind of obsession with each other since no one ever actually saw them nor touched them but it still seemed bit extreme to me. This incredible connection that they had. I'm guessing it's unique to them up to a point, but then the question is WHY. Why them? What's the whole deal, how does it work? I would have even been ok if I was told it's cause they are soul mates or whatever but I would have liked this to be addressed more fully at some point.Now with that out of the way, I loved this book! I can see some people not liking the way the romance was going, but for me, in this case it just worked for them. One a broken assassin, the other a meek girl always searching for some kind of connection with someone. And it's not like they were professing their love to each other right away, that came much later, which is why it made it ok with me. Plus the way Nix kept trying to make it up to Claire and Claire kept trying to help me heal. It was beautiful.I hadn't expected this book to be quite so dark, but I didn't mind. There was a lot of just messed up crap going on and all the stuff they did to Nix, I'm surprised he hadn't gone completely psycho by then. Loved how we had both of their PoVs, so we could see what was really going on inside their heads all the time. The development of both Nix and Claire was well done, loved how Claire finally took a stand for her and stopped waiting for things to happen and made them happen instead, and how Nix started coming to terms with what he had done.Really liked how they explained everything, the energies, how they worked, why it happened (although this cause have used a bit more fleshing out). How the Nulls and the Nobodies energy interacted with each other, the faded and the disassociation.With that ending I'm not sure if there is going to be a second one or Barnes just meant it as an open ending. I am hoping she will revisit this world, cause I for one was fascinated.