a move personally made up from the batwing, a cruel joke, mostly done by other teenagers, where you take your scrotum, spread half of your sac out with your hand, and cup the other nut in your hand like a brain. takes a while to get right, but when accomplished, is better than the batwing
I flashed robert with the bat brain, and he threw up!

Adam scared a kid with the bat brain.

by bodhi williams March 25, 2008
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When a person/persons hangs from the ceiling by their feet which then a male proceeds to put his penis in their mouth and continuously aggressively fucks her throat until he cums down her sore airways.
“Hey Nathan, I wanted to give my girlfriend bat brain last night but she was too heavy and she snapped the rope
by @kinggy May 9, 2020
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