100NL KK overpair OOP on drawy board

[BevillTheDevil]

Villian is 48/13/3.3 after 30 hands. Seems pretty awful. A few hands before he called a raise on the turn w/ a gutshot draw so def a chaser...I wasnt quite sure what was best on turn here.

Full Tilt Poker
No Limit Holdem Ring game
Blinds: $0.50/$1
6 players
Converter

Stack sizes:
Hero: $100
UTG+1: $197.60
CO: $124.60
Button: $100
SB: $98.25
BB: $100

Pre-flop: (6 players) Hero is UTG with K[img]/images/graemlins/heart.gif[/img] K[img]/images/graemlins/club.gif[/img]
<font color="#cc0000">Hero raises to $4</font>, UTG+1 folds, CO calls, 3 folds.

Flop: 8[img]/images/graemlins/heart.gif[/img] 6[img]/images/graemlins/heart.gif[/img] 4[img]/images/graemlins/diamond.gif[/img] ($9.5, 2 players)
<font color="#cc0000">Hero bets $9</font>, CO calls.

Turn: 5[img]/images/graemlins/diamond.gif[/img] ($27.5, 2 players)
Hero ??