First time I saw this cover, I thought this book would be a adult book, with some sex scenes and everything, but when I opened it, it was a YA book. Ok, no problem. I like YA, but I didn't like this book that much. 
 The book introduces us to Luc, a demon who has the objective of marking a certain person, so she/he would go to hell, when she/he dies, so for that, he enrolls in the High School of his prey, and starts to mix with the crowd. After a little while, he gets paired with Frannie, a common girl, which he gets attracted almost immediately. I know that we've things like love in the first sigh, but if you're a demon of more than a 1000 years, with the rage and hate for your only company, at the least you should have taken a little while to start to think in things like "I am utterly determined to make her happy." or "I don't want her to get hurt." Are you sure that you're a demon and not a infiltrate angel in the hell? I mean... YOU'RE TOO GOOD TO BE A DEMON! And too normal too. 
 After Luc, we've Frannie the heroine. She was a heroine that sometimes I liked and sometimes I wanted to smack her head in a wall. I know that you can be confused about to hot guys that seems to like you and everything, but after you hooked up with one of them, it's weird to go in the other guy's house and kiss him. This isn't right. 
 The last one of our main characters is Gabe, the human form of the Archangel Gabriel. Gabe was the... right character. He acted like a angel. Of course, he had his temptations throughout the book, but it wouldn't be fun if he hadn't, no? 
 Ok, the book is write in the POV of the main characters, but why Gabe's POV wasn't show? I would have liked to see his thoughts and his reactions, but besides that I like the POV thing. Luc and Frannie POV are something continuous, what means that the other POV starts where the other ended. That was good because, reading the same scene over and over again, just to show differents POV is annoying, at the least to me. 
 Well, in the overall the book was pretty good, and I want to buy the next one, Original Sins, which is going to be released in July.