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1.
that awkward moment when a curtain is blowing in the wind, and hitting against the wall, simulating the sound of ball slapping during sexual intercourse.
When a curtain is blowing in the wind through a window, and the curtain hits against a wall, producing a sound similar to what your balls make when you are having sex. Also known as Curtain Fapping
by MissLegal May 23, 2012