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1 definition by DragonBitch

 
1.
M.B
Morning Boner.....Some Guys Find This extremely annoying... Other are happy cause it means you get to fuck in the morning if you have a gf or bf
Sister: Good Morning
Brother: Oh Shit
Sister: What's Wrong?
Brother: I've got a M.B that wont go away
Sister:Sorry Can't Help You In That Department
by DragonBitch January 03, 2007