Three: One to screw it in, and two to talk about how much better it is than with a man.
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Take away his credit card
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Five. One to screw it in and four to tell him how bitchin' he looked doing it.
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None, because people who glow in the dark don't need light bulbs.
Note: Topical to the Chernobyl Reactor disaster of 1984.
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Does it have to be a light bulb? I've got this neat candle holder...
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To the dock.
or