Werewolves change into wolves when the moon is full. But Edward's curse only allows him to be human when the moon is full.

Alone and despairing, Edward hides himself away from the world. He's scraped out a meager existence for himself for almost a century in the forest he's grown to love and call home. But in the depths of a terrible winter, he stumbles across clues from the life his mother left behind in Faerie. The truth may give him the answers he needs about the source of his birthright...and the curse that holds him captive.