After taking a painful shit you end up walking like a mummy and/or zombie in order to not upset your asshole.
Wife: Are you okay dear?

Typical guy/husband: Yeah but I just took a big Mummy Shit and it hurts so bad!

Wife: Pig.
by AzzaCadabra October 29, 2010
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When someone likes to get shit on in sex (insanely gross) the person getting shat upon is the shit mummy.
Sarah was John's shit mummy.
by Sslide June 10, 2017
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