The act of forcing a fleshlight (unlubricated) into your partners asshole. The best time to do such an arousing act is when your just about to finish and instead of cuming inside of her, you force the fleshlight inside of her ass and you cum in that instead of her vagina. Most likely she will scream in pure pleasure (which is commenly mistaken for a scream of pain and anguish). But do not let that fool you my friend...she will remember that pleasure for years to come.
Amy: "Hey Jessia."
Jessica: "Yeah?"
Amy: Did I ever tell you how Blake bi-vaged me last
night?
Jessica: "No! You never told me that!
Amy: "Yeah, it was amazing! Iv'e never cum so hard before!"
Jessica: "Golly, if only I could get Dylan to bi-vag me.
Amy: "You gotta! bi-vaging is the best!"
by MasterBlake March 28, 2011
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