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1.
1. anal sex in an un-clean ass
Mike mounted Lisa for some anal but pulled out when he discovered he was mud riding.
by Bud E Love May 05, 2003
 
2.
A sexual position involving four people (two men, two women). The two men are facing eachother while sitting down and the ladies are taking it up the ass while using a two-way dildo.
Who wants to go Mudriding ?
by danah February 27, 2008