The act of masturbating and thinking of animals.
Person 1- So today i decided to masturbate to something different like..Beasting off.

Person 2- whats that?

Person 1- It's where you masturbate and think of animals while masturbating.

Person 2- Really?! OMG! I'm going to go try that right now!
by D. Schlosser February 25, 2008
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