When a man inserts his flacid penis into a woman and then becomes erect inside of her.

For effect, the man may tug his scrotum as if he is releasing helium into his dick.
Jill: Why did you stick your floppy dick in me?

Jack: Wait for it.

Jill: Oh my!

Jack: That's my helium balloon, baby.
by Fozter March 26, 2010
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