3 betting with 2nd nut straight when flush hits on the river

[Nemesis]

Same uber fish from earlier post. He likes to bluff, but have never been bluff raised by him before. He doesn't like to fold after the flop it seems.

PokerStars 3/6 Hold'em (5 handed) converter

Preflop: Hero is BB with 4[img]/images/graemlins/heart.gif[/img], K[img]/images/graemlins/spade.gif[/img].
UTG folds, MP calls, Button folds, SB folds, Hero checks.

Flop: (2.33 SB) 9[img]/images/graemlins/heart.gif[/img], T[img]/images/graemlins/club.gif[/img], J[img]/images/graemlins/heart.gif[/img] <font color="blue">(2 players)</font>
<font color="CC3333">Hero bets</font>, MP calls.

Turn: (2.16 BB) Q[img]/images/graemlins/club.gif[/img] <font color="blue">(2 players)</font>
<font color="CC3333">Hero bets</font>, MP calls.

River: (4.16 BB) 7[img]/images/graemlins/heart.gif[/img] <font color="blue">(2 players)</font>
<font color="CC3333">Hero bets</font>, <font color="CC3333">MP raises</font>, <font color="CC3333">Hero 3-bets</font>, MP calls.

Final Pot: 10.16 BB