Often said by older males who are indeed high/drunk,when they can't get another beer or they are kidding around with their buddies. Other times just used to be a jackass

It's actually just the word motherfucker backwards,hence the drunkness or highness

Sidenote;
Sometimes tooken offensive
Beware.

when you are arguing with your mom that you should be able to stay overnight at your freinds house and she only says the answer is no even though all the circumstances allow it.

Mother who fucks.