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1.
Back Side Distortion Factor. The phenomenon occurs when you see a female from the back and she is stunning. This could be because of the way her hair is done; or, more likely, how nice here booty is. Then she turns around and she is not only a tad on the chuncky side, but has a face that would make the most hearty of men run in fear.
"Wow, check out that girl at your 12oclock. She is FINE!! I hope it's not BSDF."

*she turns around*

"O God, I'm gonna go puke!"

by MilkMan99 April 17, 2008