A hemorrhoid butthole with dried blood.
A patient came in today complaining about hemorrhoids, when they pulled their pants down, it looked like a rusty muffin.
While having anal sex in a doggy style position, the man removes the shit from his dick and wipes it down the lower of the other persons back.
Dude, (he/she) shit on my dick, so I gave (him/her) a Canadian beaver tail.