Finnick feigns injury when she drives her knee in against him, a blow that would have had more substance if they had been on land; he dreads ever having take a serious injury from her -- because she could certainly do it. (Even though there had been plans for them to be allies in the Arena for the Quarter Quell, he'd had nightmares for a bit about her killing him. He'd woken up in a cold sweat on more than one night with the image of an axe being thrust into his stomach seared onto the inside of his eyelids.)

He pushes back from the wall a little once she starts to strip down, giving her some space. She's probably the one that uses nudity as a better weapon that he does.

"A city?" Finnick smiles as she talks. "Not what I would expect from you, Jo."