Cowboys: Well-played?

[SomethingClever]

Party Poker 0.50/1 Hold'em (9 handed)

Preflop: Hero is BB with K/images/graemlins/heart.gif, K/images/graemlins/spade.gif.
UTG calls, UTG+1 calls, MP1 calls, MP2 folds, MP3 folds, CO calls, Button calls, SB completes, <font color="CC3333">Hero raises</font>, UTG calls, UTG+1 calls, MP1 calls, CO calls, Button calls, SB calls.

Flop: (14 SB) T/images/graemlins/spade.gif, J/images/graemlins/heart.gif, 4/images/graemlins/spade.gif <font color="blue">(7 players)</font>
SB checks, Hero checks, UTG checks, UTG+1 checks, MP1 checks, <font color="CC3333">CO bets</font>, Button calls, SB calls, <font color="CC3333">Hero raises</font>, UTG calls, UTG+1 folds, MP1 folds, CO calls, Button folds, SB calls.

Turn: (11.50 BB) 2/images/graemlins/spade.gif <font color="blue">(4 players)</font>
SB checks, <font color="CC3333">Hero bets</font>, UTG calls, CO calls, SB calls.

River: (15.50 BB) K/images/graemlins/club.gif <font color="blue">(4 players)</font>
SB checks, <font color="CC3333">Hero bets</font>, <font color="CC3333">UTG raises</font>, CO folds, SB calls, Hero calls.

Final Pot: 21.50 BB
<font color="green">Main Pot: 21.50 BB, between SB, Hero and UTG.</font> &gt; <font color="white">Pot won by UTG (21.50 BB).</font>

Results in white below: <font color="white">
SB shows Ad Qh (straight, ace high).
Hero shows Kh Ks (three of a kind, kings).
UTG shows As 9s (flush, ace high).
Outcome: UTG wins 21.50 BB. </font>

[SomethingClever]

I was the BB; I raised preflop.

I'm wondering about the river. It's an obvious bet-out, but when I was raised, I figured someone was slowplaying a flush on the turn.

Does anyone 3-bet the river?

[SomethingClever]

What the heck? I was responding to a comment that disappeared!

[Matty]

I think this one comes down to a read. Without a read, I think I'd have to call the river raise.