When a girl has the distasteful habit of wiping back to front instead of front to back like a proper lady.
You really don't want to go down on Sandra. i heard she has a nasty mud muffin.
by junglefeverjake February 27, 2015
Excrement; turd (see fudge dragon)
"My neighbor never picks up after his dog. Every morning on the way to get the paper I step in a fresh batch of mud muffins."
by R. Bowers October 07, 2012
When a girl takes a shit, wipes ass into her vagina and then you eat her out...
dude your mom is FOREVER doing mud muffins in the dark...
by y8 February 19, 2009