She does indeed manage to hit Hinata square in the back of the head, causing him to stop and turn around to see what he had been hit with. Sitting right by his feet is the gymnastics ball, which he picks up immediately and starts to scan the crowd to see who it could belong to, not very amused at all by being hit by it. People really need to watch where they're throwing things when there's this many people around, seriously.

But when he hears the girl speak up, it becomes pretty clear that it's hers, and it's highly likely that she threw the ball at him on purpose. This revelation only serves to piss Hinata off even more. He could take the immature route and just throw it right back at her, but her ninja friend probably won't appreciate that, plus he's a better person than that, anyway. So he'll approach once more and walk directly up to Kodachi, holding the ball out to her.

"Here."