There's a laugh at that — okay, Luca has a point. Maybe it would be pretty much cheating, but still... it's impressive that the kid's able to swim like that.

He continues to follow the younger until they come to a stop, Peter's long arms slowly moving through the water to keep himself afloat. He glances downwards at Luca's words, thinking about it. Something in him (it's Paimon) knows he'll be okay. He couldn't explain what it is, just... he isn't particularly worried.

"Don't worry, I'll just go down enough where it's still safe. If it seems too deep, I'll come back up."

...He has no idea that he won't need to come back up at all. Though the demon's stirring a bit more, and might end up taking over just to be on the safe side.