Character Analysis
Most of the fellows in the band are minor characters and kind of move around together in a group. They are fun-loving, trash-talking, musical masters. They are good at what they do. They have to be, or Calloway would fire them really fast. Like they say to the Thug all the time, "Mr. C changes drummers the way most folks change their drawers. What you see in front of you is a man on borrowed time" (13.101).
The Thug is not as nice to Bud as some of the others in the band are. He thinks it's fun to pick on Bud, and he's a bit rough around the edges. Mr. Jimmy is as old as Calloway and is his close friend. He is kind to Bud and fair, but doesn't show up much in the book. He is the first one to invite Bud to dinner and try to get things sorted out. Dirty Deed is the only white guy in the band; he doesn't interact much with Bud. And Doo-doo Bug is also kind of a placeholder; he's part of the group but doesn't do much besides make the band bigger.
The main point is that these guys, together with Miss Hill and others, make up a new family for Bud. In the story, they're more important as a group than as individuals because together they represent the new home Bud has found.