[wyrd]

I think you should fold. The pot isn't really all that big for no limit. It's a typical raised preflop sized pot on the turn. Unlike the advice given above, your hand is not "too good to fold." We do realize that KK is only a pair right? How often does your pair win after a player suddenly wakes up on the turn and shows aggression? Given that, and the fact that the pot isn't that big, I'd fold.

People here are saying to call, then call another small sized river bet. There's no guarantee he's going to make another small bet. If another club comes off, you're dead, and wasted $3 hoping to get a cheap showdown. If he bets the pot on the river, same situation, you're probably dead, and wasted $3. In fact, if he bets anything on the river, you're beat, plain and simple.

Realistically what could he be bettering here that you beat? It's not like the turn put an overcard on the board and now he's betting top pair. I think 2 things are most likely; a set of tens, or a flush. If he had top pair on the flop, why would he not bet it? I think this discounts JT and two pair. However, he could have 56, but I believe that is also unlikely given he didn't check/raise the flop.

The set of tens make sense. He called your raise with pocket tens, saw an overcard on the board, so he called your seemingly continuation bet with second pair. You may or may not have that jack, so he wants to find out on the turn. The turn gives him a miracle, but puts a possible flush on the board. He now has a set, but you may have a flush. So he bets small hoping to find out cheaply, or to at least see the river cheaply hoping to hit a boat, that way he won't have to worry about the flush anymore.

Now the flush also makes sense. He calls your raise with a couple of suited cards. Being out of position, he checks the flop and calls your pot sized bet, which is typical of anyone on a flush draw. The turn gives him a flush. Now he bets small. The small bet is a bit curious. Maybe he's got the nuts and wants to price you in, afraid that you may check behind him (which is working given the advice others are giving you). If he had a small flush, I would expect a pot sized bet, that way he could make you fold an Ace of clubs, so he doesn't get rivered.

In any case, that's how I see it.