Definition: When a rape victim has clenched their butt before the rapist has a chance to penetrate them.
Example Sentence:

Dave: "Hey bro, last night I picked up a cute high school kid but he was totally pre-clenched!"
Catherine: "Ahhh shucks, maybe next time... keep it up!"
by WakeyWakeyHandsOffSnakey October 21, 2018
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