Three High school girls go to the same bathroom every 4th period and each time they gossip and spill tea, and do their makeup, and each time before they leave they write a message on the mirror with their lipstick.
Sometimes they write the name of the boy they like, sometimes draw a hand giving the world the finger. every day at the end of the day, the sad old janitor comes in to the bathroom and scrubs the lipstick away.
eventually after many days, the principal calls the 3 girls down 5th period after a student snitched. the principal takes them to the bathroom and calls over the janitor.
There is already the frowning face drawn in lipstick from 4th period and the girls looked at it and sneered and laughed.
the principal says “apologize to the janitor for making him clean up your mess!” and the girls just rolled their eyes.
so the principal says to the girls, “now watch what you put the poor janitor through every day!”
and so the janitor shrugs, takes his sponge, goes to the toilet, submerges the sponge in the toilet, comes back to the mirror and scrubs the lipstick away.