Hourglass by Claudia Gray

I just read this book in a day and half. It was very good, with several plot twists and a cliff-hanger ending. This is the third in what looks to be a four-book series which began with Evernight and continued with Stargazer. It is the continuing story of Bianca, born of two vampires yet still mostly human, and Lucas, a member of a cell of Black Cross vampire hunters. They met at Evernight Academy, a school for vampires to learn to fit into society. They fell in love and eventually ran away together. Their love is strong enough to survive anything, or so we hope. I can't wait to read book four, Afterlife.