my brother and I did this a few years ago, but we did an Andy Kaufman style bit that only 1-2 people out of 50 or so thought was funny.
My brother is 6'5 280 lbs and was pretending to be my caregiver. I of course was in a wheelchair pretending to be retarded.
We'd been at the club for an hour before our turn and people had seen my brother blow up in anger at me, with a couple of people actually coming to my defense. (leave him alone! can't you see he's scared?)
When we got on stage, my brother told a couple of dumb jokes to piss people off, and then turned his anger at their response on me. It ended with me falling out of my wheelchair and a couple of bros threatening to kick my brother's ass.
Someone also called the cops, and I had to come out of character eventually, which made people even more mad.
Obviously much funnier for us than the crowd.