As far as stand-alone novels go (books that aren't part of a series/trilogy/duology), this one is really good and definitely one of my favorites. 
 At first I was sort of put out when I started the first few pages because I thought that I would get a chance to get to know every one of Darcy's friends little by little instead of just shoving them at us and reading what would be a normal everyday conversation between them. That sort of made me want to stop reading, but I decided to go on to see if I was being stupid for wanting to quit and so when we met Conn, I thought it was the most cliche and cheesy introduction about him but I liked him. And since the summary mentioned something about how he betrays Darcy, I decided to keep on reading to see how the book would turn out. 
 Let me just say I LOVED this book. 
 It was unique and realistic, excluding the part about her being a Shade and all that. Darcy being an orphan/foster teenager with a sad and weird past was well written and really added to her character development. The pacing was good and both worlds were well written. The idea of Conn's world being an alternate dimension, sort-of copy of Darcy's world was interesting and must have taken a great deal of imagination and thought to be able to write something normal and sane for the readers to understand. I wouldn't mind going to visit Conn's world though, no matter how different and sci-fi it sounds! (view spoiler)[It was an interesting take the idea that the bad things like deaths and massacres were caused by Shades in the real world but never happened in the other world thus an alternate dimension was created after The Great Chicago Fire of 1871 that never happened/was stopped in Conn's world (hide spoiler)] 
 Learning about the Shades and what they do, made me feel sad for Darcy, who all she wanted was to find out about her past and when she finally got the chance to know about her heritage and herself, the big, ugly reveal turned out to be that Shades were murderers and evil. Since Darcy was nothing like this, she felt horrible that she could be tied to a horrible heritage like that and spends her time trying to stop whatever big evil plan the Shades have in mind. 
 No instalove, I liked that they got to know each other by hanging out and spending time together (view spoiler)[before they ever kissed... And then the thing happened, the betrayal (hide spoiler)] and then the time they spent together in Conn's world, I loved it! You could tell how much he cared for her even if he never said anything he just showed it. The love triangle: well, it wasn't much of a love triangle. Orion was the only Shade her age that she knew and although he made advances towards her, Darcy was so not interested in him (view spoiler)[no matter the times he kissed her (hide spoiler)] and so he sort of faded into the background of non-importance, at least to me. Now, her friends also made a guest appearance in Conn's world and that was interesting enough which was definitely unexpected and one of my favorite parts of the novel. 
 All in all, I really enjoyed this book and it's definitely something I would recommend to other fellow readers.