Sinner by Maggie Stiefvater
At first, I was a little bored with this book because it seemed to be a thinly veiled, angsty teen, love story where nothing happens. But I really like Stiefvater (especially her writing style) so I persevered and I am glad I did.
Yes, Sinner is a love story featuring a werewolf but underneath it is so much more than that. It is a brutally honest portrait of a city (L.A.). It is a study in addicts and addiction and grief and guilt. It asks a question of humanity: do human beings ever truly change?