KK facing a stop & go

[VarlosZ]

PartyPoker $2-$4 NL, 10-handed. Villain in UTG with $380, I have him covered. He's been playing pretty conservatively; in an hour at the table, I haven't seen an early position raise from him yet. In a previous hand, I pushed him off a big pot when the turn put a flush on the board, and we'd been talking about it since -- I claimed not to have had the flush.

I've got K[img]/images/graemlins/diamond.gif[/img] K[img]/images/graemlins/club.gif[/img] UTG+1. UTG raises to $12. I call, everyone else folds.

Flop (pot=$27): 9[img]/images/graemlins/club.gif[/img] 5[img]/images/graemlins/spade.gif[/img] 4[img]/images/graemlins/spade.gif[/img]

UTG leads for $20, I raise to $60. UTG calls.

Turn (pot=$147): 2[img]/images/graemlins/heart.gif[/img]

UTG bets $100, leaving him with about $205 in his stack. I . . . ?