[action]
[He laughs a little at that - considering how some people talk about it she's not entirely wrong.]
It's an ocean current. Back home the world is divided in... [He pauses, shifting a little closer to her before laying out his hand in front of her, palm up. It'd be better with pen and paper but this'll do as a makeshift map and so he draws out the lines and oceans across his palm as he speaks.] ...it's divided into four major oceans: East Blue, West Blue, North Blue and South Blue. They're divided from the North-East to the South-West by the Red Line - it's a great continent that stretches all the way around the world. Perpendicular to that we have the Grand Line, with the Calm Belts parallel to it on either side.