[Gon swims behind him, kicking off with his feet toward the rocks. Killua's comment makes him furrow his brows but he lets it go, as if he let his breath go he might drown. For the same reason, when Killua asks about the fish, he doesn't answer but nods. He points at a group of yellow and black fish.

Killua must be gloating about being the only one who can talk, he thinks.]