It is the act of taping ones penis to ones leg with either tape or cling film and wanking with his leg like a chimp.

The main advantage of this is that one can still eat and drink at the same time like a Sir.
Sir 1 "Dude we used so much tape and cling film"
Sir 2 "What having a chimp wank?"
by Bashtoe April 1, 2012
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