nut flush on river on paired board....

[drbk2]

Good $15/$30 game at NYC club I have mentioned before...

Loose aggressive player in MP3 who has a lot of respect for me raises. Cut off is a guy who has been really weird all day. He's thrown in some complete stupid bluffs against unbluffable calling stations and I saw him call down a few times with huge hands. Anyway he cold calls. I three bet on the button with AdJh. MP3 and cutoff both call.

Flop: Qd Td 7d. MP3 bets, Cutoff calls, I raise, MP3 three bets, cutoff calls, I call.

Turn: 6s. MP3 bets, Cutoff calls, I call.

River: 7d. To my surprise, MP3 bets again. Now cutoff comes to life and raises. What do I do?