Diarrhea Cutter

An anus.

Stupid random woman- "Hey look it's my dog."

Stupid random woman- "Lets rub the dog's belly."

Stupid random woman- "Hmmmm my dog is acting strange oh I know let's check his diarrhea cutter!"

Intelligent dog- "Oh man here it comes !"

Stupid random woman- "HOLY DIARRHEA CUTTER, LIQUEFIED FECES IS EVERYWHERE AND MY WHOLE $1 PRE-WORN SHIRT IS RUINED ! NOW I HAVE TO SPEND THE NEXT 20 YEARS POWER WASHING ALL PARTS OF MY MOUTH !"