[Killua frowns as he eyes the note. This is suspiciously familiar. He does not, however, feel threatened, so with a light kick of the tree, he notes the new coordinates and is about to take off when he hears Al speak up.

He turns around to face the older teen with childish condescension.]

It's a pirate thing. It's a way to tell someone they're guilty and there's no way they can get out of being punished for it.