The mark left on a boy/girls undergarments if they don’t wipe their bum properly.
The mark left is similar to that of a butterfly print made when children just with a poop colour and smell.
Me: Oscar have you been wiping your bottom properly?
Oscar: Yeah
Me: Well why are there butterfly prints in your pants?!?
A stain a woman imprints after sex with her vagina on your furniture or other items(bed, couch, carpet, etc.) that resembles a butterfly.
When Marry got off my bed after having sex she left butterfly prints on my sheets.