The inner lining of the anal sphincter and subsequent musculature of the lower intestine.

An article of personal protective equipment one would wear over the arm while engaged in the artificial insemination of livestock, or while committing other questionable acts of sodomy.
Make sure to don your butt sleeve before going elbow deep!

I’ve been cutting some repugnant gassers lately, I think something died in my butt sleeve.
by WolfBone January 12, 2012
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