A poop smeared ass crack. Usually the result of improper wiping or cleaning. May also be the result of a shart or fart in which you get more than you bargained for.
I started to go down on my girl last night until I discovered she had a nasty mud gutter. Then I got the hell out of there.
Or
Man, I shouldn't have pushed so hard with that last fart. Now I got a mud gutter!
Or
Man, I shouldn't have pushed so hard with that last fart. Now I got a mud gutter!
by The Gronk March 3, 2010