this may shock you, but most people wipe their butt after they've pooped and sometimes they get some on their fingers
in first place, if your poop is making a huge mess when it gets out, something is wrong or inside you or with your diet
second place, i can't see how the top of your fingers could end up in the middle of your poop, i guess or you are not using enough toilet paper or you have motor coordination issues
change the subject
but its naturally genetic for some people to have that though..
