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1.
this is when you are balls deep in a girl, just tearing her shit apart and right when you're going to cum you pull out and spew all in her belly button, then you take your cock and stick it in the belly button and rub all the cum up to her mouth and when you finally arrive at the mainland or her mouth you take your roters and slap 'em all around.
dude, i totally just mainlanded that bitch.

hey sexy, ever been mainlanding?
by Corporal Hymen April 20, 2009