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1.
A masturbation technique where a male masturbator rolls back onto his shoulders, with his body in the air over his face for the purposes of either giving himself a cum facial or eating his own load. Since the masturbator is essentially upside down, he takes on the appearance of a sleeping bat.
"I'm not flexible enough to suck myself off, so in order to cum in my own mouth, I have to resort to bat jacking"
by Char H January 08, 2006