[Makoto's going to be too good at this soon-- or perhaps Oona is just simple to read. Her desires are rather simple ones, and it isn't that hard to twist conversations in the other person's favor when she's involved. Curiosity wins out over any lingering feral want to hunt what enters her waters, and she perks up.]

Ah, yes, that is true. [Her eyes spark with challenge, remembering her earlier humiliation at losing to Rin's swimming. That had been her fault, she knew that. She'd been cocky and her ego had gotten in the way, but this time... This time she was fully prepared to win.]

Scared? [Incredulous she looks at him like he's grown a second head] You may have swam since you were young, but I was born of water. [She throws her hand against the water, splashing at him with a smirk] You will not be laughing when you lose!