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A Seventy one is done while performing the Sixty Nine and one of the Participants put two of their fingers in the other person's ass.
The other day I caught Bill and Jill doing the Seventy one.
by moorebounce February 17, 2010
A seventy one is a sixty nine with each others thumb up each others ass
Chad and Trent pulled a seventy one last night
by Goof April 10, 2005