One who will do pretty much anything for their marching band. Usually, but not always a drum major or color guard captain, most of the time forced into "helping out" (such as opening doors, handing out drill sheets and/or schedules, demostrating proper marching technique, etc.) by the band director. Sometimes they come in the form of aspiring drum majors or color guard captains, hoping to butter up to the director.
"Hey why is Mary handing out all those band schedules?"
"Well, she wants to be a drum major. She could be next year-she's already a band bitch."