Jacob. Definitely Jacob.
He's strong, funny, couragous, and just plain awesome. Plus, he actually has a personality. He has lots of personalities really, out of all the characters in Twilight, I believe Jacob changed and grew up the most from start to finish. At first he was just a happy and carefree kid. Then he became more responsible, brave, and gradually bitter but still kind of happy. But then, all that happiness is torn to shreds when he loses Bella. Jacob's a good and caring person. When Edward left Bella broken, Jacob fixed her up, made her happy, gave her something to be happy about. Even when he becomes a werewolf, he manages to stay close with Bella, and they're happy. But then Edward returns, and Bella runs right back to him leaving Jacob in the dust. And Edward being a vampire restricts Jacob from seeing her. But even so, Jacob doesn't give up, he refuses to lose Bella, he refuses to lose someone he cares so much about. Even when he finds out that Bella wants to be a vampire, he still doesn't give up, he fights harder, he tells her his feelings for her. He loves her. So he fights and fights, he gives it everything he's got, he tries everything he can, and he STILL loses her. Even when she loves him back, he STILL loses her. He gave it everything he had, there's nothing else left. Now Jacob is completely heartbroken, he's depressed, enraged, bitter, in pain, and all his happiness is gone. Poor Jacob. The only thing that could save him from his pain is imprinting. It's like his pain was so bad, Meyer had to force happiness on him. Jacob deserves better than that. He's an awesome character with a broken heart. That's why I like him and Twilight Saga would suck without him around.