alejandroninja's definitions
While fucking a girl doggystyle, preferably, in the ass, you thrust extra hard making her moan in pain/pleasure, you then shit in your hand and slam dunk it in her open mouth.
E.g.: "Dude, i totally shanghai slamdunked the entire Chinese gymnastics team. That's why they all have sour looks on their faces!"
by alejandroninja May 9, 2014
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