Who is Bear/Orson Hrothgar from Crispin: The Cross of Lead and what is their importance?

Bear/Orson Hrothgar is described as sweet and easy going, at least until he is upset......then he becomes hostile and ferocious. Bear cares for Crispin after his mother's death. He is a juggler by profession, and he travels from town to town earning money. At first, Crispin serves as his servant, but it becomes apparent that Bear is actually very lonely. As the story progresses, he comes to view Crispin as family and cares for him a great deal.