A particular breed of snake that dwells in the household bath or shower. whilst the bath or shower is in use the snake recoils back into the drain, and if you are unlucky, will spring out of the drain and sink its fangs right in your sphincter.
as a person is going for a shower "watch out for the sphincter snake."

after having been bit "AH! THE SPHINCTER SNAKE BIT ME!"
by Sparkyyyyyy August 9, 2005
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