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1.
Originated in Brixton (London). A type of group sex activity developed by contorsionists in the early part of the 21st Century.

A box is placed in the center of a ring of people, where a contorsionist climbs in and is then penetrated through various well placed holes in the sides of the box.

Box banging is not gender, or sexual orientation specific.
that was a right good box bang dad
by Box banger UK January 11, 2011