Lauren Kate's Fallen, Torment, and Passion on audiobook in the car and I've been enamored.
In the first book, Fallen, we meet seventeen-year-old Luce, a new student at the reform school, Sword and Cross. But, Lucinda isn't your typical reform student. She's actually a good girl, haunted by shadows, and the death of the first boy she ever kissed. I don't want to give too much away, but let's just say there's eternal love, kissing, angels, demons, and in the second book, Torment, Nephilim.
The one thing I've really enjoyed about reading this series is how Lauren Kate is the master of slowly releasing information, always leaving the reader in suspense. And she only gets better at it in the second and third book.
If you're looking for a good series to get wrapped up in, I definitely recommend Lauren Kate's Fallen Novels.