I call. Interesting river against a hudge fish NL50

[xoom]

No Limit Holdem Ring game
Blinds: £0.10/£0.20
4 players

Stack sizes:
UTG: £17.45
Button: £63.72
SB: £47.67
Hero: £23.81

Pre-flop: (4 players) Hero is BB with J[img]/images/graemlins/diamond.gif[/img] J[img]/images/graemlins/club.gif[/img]
UTG calls, Button folds, SB calls, <font color="#cc0000">Hero raises to £1.2</font>, UTG calls, SB folds.

Flop: 4[img]/images/graemlins/spade.gif[/img] K[img]/images/graemlins/heart.gif[/img] 9[img]/images/graemlins/diamond.gif[/img] (£2.6, 2 players)
<font color="#cc0000">Hero bets £2</font>, UTG calls.

Turn: 6[img]/images/graemlins/club.gif[/img] (£6.6, 2 players)
Hero checks, <font color="#cc0000">UTG bets £3</font>, Hero calls.

River: K[img]/images/graemlins/club.gif[/img] (£12.6, 2 players)
Hero checks, <font color="#cc0000">UTG is all-in £11.25</font>, Hero calls.

Results:
Final pot: £35.1

Villain is playing something like 75/50/4.5 over the first couple of orbits. I check the turn here because villain will bet with any pair and there's no draws to worry about. I don't want to bloat the pot either against an aggressive lagtard.

When the K hits on the river I instantly think that my jacks are good. It is now less likely that he is holding a K. Check/call is still the best option, since he probably will fold without a king , but bet any king and hands that I beat.

How did I play this?