Apparently not that rare phenomenon when you weigh yourself up, then you take a shit, weigh yourself again and you notice you are slightly heavier than you were before the act.

The ultimate negative poo, in turn, is when you actually weigh yourself up during the act and you see yourself gaining on weight on the scale.
- Cannot be. Right before shitting it was like 170 lbs and now its 175!
- Negative poo at its finest.
by krd April 18, 2014
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