n6mer
A n6mer is a troublemaker who thinks the whole world is their toy box and they're the only one who knows how to play. They'll make your life a mess just for fun.
My neighbor is a n6mer. He put a whoopee cushion on the mailman’s chair.
In class, a n6mer whispered secrets to the ceiling.
My dog is a n6mer. He barked at the mailman like he was a thief.