[I.Rowboat]

PF: I don't like the UTG limp with a vulnerable hand like 99, as I wouldn't want to invite a lot of callers with this hand OOP, and I think the hand is easier to play when you come in with a raise. However, I can see limping here sometimes to mix up your play. As the hand went down (with only three to the flop), I might go ahead and limp re-raise here as a semi-bluff, as it implies that you hold a big hand and puts more pressure on the other players, esp. the BB, to fit-or-fold on the flop.

Flop: That is a very dry board. Flop play is fine, I assume the BB folded to the double bet? At this point, given that the CO just called your 3-bet, what do you put him on? Overs? Given your action to this point, what can he reasonably put you on? Some sort of J I would assume, maybe AJo or KJs/QJs?

Turn: If he had overs, this had to help him, and unless he puts you on exactly KJ, I don't think he can believe the K helped you. I think the turn bet is desperate, but I would probably make it, too. The only other line I can think of would be to c/r the turn, but given his aggression to this point and his relatively low AF, I think a c/r will either get called or re-raised. So it's a toss up between bet/fold and check/fold. If I do bet and get called, I am definitely checking the river UI.