Rivered set vs check-raise 3/6

[chiaroscuro]

Villain is 26/16/1.75, I've been playing slightly loose and c-betting pretty much constantly. Stacked villain earlier on and he started to tilt but seems to have calmed down since.

Party Poker No-Limit Hold'em, $ BB (6 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: 2+2 Forums)

CO ($467.65)
Button ($687.18)
SB ($136.76)
BB ($694.50)
Hero ($1096.95)
MP ($578)

Preflop: Hero is UTG with 6[img]/images/graemlins/club.gif[/img], 6[img]/images/graemlins/diamond.gif[/img]. SB posts a blind of $3.
<font color="#CC3333">Hero raises to $21</font>, <font color="#666666">4 folds</font>, BB calls $15.

Flop: ($45) K[img]/images/graemlins/club.gif[/img], 8[img]/images/graemlins/spade.gif[/img], 9[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
BB checks, <font color="#CC3333">Hero bets $35</font>, BB calls $35.

Turn: ($115) J[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
BB checks, Hero checks.

River: ($115) 6[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
BB checks, <font color="#CC3333">Hero bets $100</font>, <font color="#CC3333">BB raises to $366</font>, Hero folds.