DD1 & DD2 were "face painting" each other with markers. They were mighty pleased with themselves of course!

DD2 runs off to her Lola excitedly...

DD2: Lola, I can face paint you too!
Lola: I don't want to!
DD2: Why not? No need to worry, they're washable markers. That means you can wash them off! It's easy.

In fairness, seems like they thought this through before doing it.