crappy crack
Crappy Crack is when you have wiped your ass after taking a crap earlier in the day.. As a result you spread your crap higher in your crack. When you use the toilet a second time you find that you have left a skid mark on the back of the toilet seat.
You have swamp and gremlin ass and you wiped it higher in your ass crack and you sit down on the toilet seat and leave a crappy crack (toilet seat skid mark).