People Like Us by Dana Mele: review.

Mean people doing mean things. This is what this book is about. Calling names, bullying, mocking and even killing people seems to be the bread and butter of the elite boarding school Kay is attending. But don't be mistaken, Kay is no angel. She'd rather eat than be eaten and talks about murder with such an ease that makes you wonder what skeletons she may have in her own closet. The rest of her classmates, including boyfriends, are not better. In fact, there isn't a single good character in this novel, all of them are deeply flawed and therefore you won't guess until the end who the killer is.
It's an interesting novel, but not a pleasant one.