He's taken a very weird line and I'm pretty interested in what he's doing it with; he also can certainly have us beat. If our image is indeed very bluffy and floaty then definitely raise the river but without that table image I would just go ahead and flat. He could also be inducing with this sizing, but then it's just a cooler if he's got a better 9 and we could even discount some of the higher as he might choose to steal preflop with them.
I don't like your turn line, you're never bluffing ever with that sizing and if your hand does scream a 9 it's because you screamed it to him. With no flush draw out there and not much worse that will pay you off for both a turn raise and a river bet you should just flat.