Contemporary fiction. I'd heard the "twist" elsewhere, but I wish it weren't on the book jacket. What's initially withheld is withheld for a real reason, not just surprise (although I don't like being spoiled for surprises, either). It is doing things with empathy and understanding and identity that are utterly critical to the book. What I can say: It's about grief and loss, the loss of a sister who disappeared, the loss of a brother who ran away, the loss of parents who can no longer be relied upon.
It's also about the incredibly random things that happen in college.
At the moment, I like it better than Wit's End, but not as much as Sarah Canary or Sister Noon.