A sex-practice involving one party blowing into the opening of the penis (as with inflating a balloon) until the scrotum begins to inflate. It is then held there until climax is reached, at which time, the party releases the hold, & the air.

*WARNING: Do NOT try this!
Wow, she gave me one nasty Bad Balloon; my balls nearly exploded!
by The Creep1 November 18, 2010
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