Who is the "yes-sir"?
Native speaker’s answer
Rebecca
The singer is talking about himself when he says "not a yes-sir". In this context, a "yes-sir" refers to the kind of person who says "yes sir". This person always respects the rules and lets other people tell them what to do. "Yes-sir" is not a general expression, however in this context the meaning is known if you imagine the kind of person who always says "yes sir".