KK hand, against villian who just joined table a few hands ago. What's the best play on the turn here?

PokerStars No-Limit Hold'em, $0.05 BB (8 handed) FTR converter on zerodivide.cx

SB ($5.69)
BB ($3.95)
Hero ($5.11)
UTG+1 ($3.37)
MP1 ($5)
MP2 ($9.66)
CO ($12.27)
Button ($2.76)

Preflop: Hero is UTG with K, K.
Hero raises to $0.3, 3 folds, CO calls $0.30, Button calls $0.30, SB raises to $0.55, 1 fold, Hero calls $0.25, CO calls $0.25, Button calls $0.25.

Flop: ($2.25) 9, 8, 8 (4 players)
SB checks, Hero bets $1.25, CO calls $1.25, Button folds, SB folds.

Turn: ($4.75) 3 (2 players)