When your balls get sweaty and stick to your inner thighs, usually when wearing loose fitting boxer shorts that don't offer much support. Often abbreviated as BSTL
Billy was stretching his legs apart to try to get his balls to unstick from his legs.

"Dude why are you feeling your dick"

"I'm try to get rid of my balls stuck to leg"
by Scottsurbandictionary May 15, 2010
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