Definitely in New Moon...he's such a sweetheart to heartbroken Bella in that portion of the series. But when Breaking Dawn approaches, Jacob becomes such a jerk towards her. He practically drops his feelings for Bella as soon as he sets his adorable wolfie eyes on Renesmee. I love Jake, but I wish he would have handled that situation with delicacy. Eh...guess that's part of the wolf pack's imprinting process, so it can't be changed.
New Moon, cuz he is just sooo sweet and suportive to bella, but i LOVED him in Eclipse(My Fave Book) coz he fought for what he wanted and didnt stand for being let down.! :) <3 Chu Jacob!!