Sulley from Monsters, Inc.
Sulley is a reluctant overachiever who is immensely successful in what he does. He scares people for a living, and generates a lot of power for his universe. But he does have a soft side, that is revealed when he befriends a human toddler, who he names Boo. Sulley also returns Boo to her home, fighting a lot of evil on the way.