A doo-doo stain is the result of improper wiping after taking a dump. After taking the dump, when you pull your pants up.. your poop may go through your underwear and straight onto your pants/shorts/dress/shirt or whateverthefrik. You'll be humiliated in public and bye bye reputation :)

Make sure you wipe that butt kids!!
billy got doo-doo stains on the back of his pants
by lovelypeachesonthetrack August 2, 2018
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