*grunch*

TURN - hero bets. If he's slowplaying the K, you can check/call the river. As you said, he could have the K or an underpair...but you don't want to give a free card to that underpair (or some weird backdoor flush draw.) If you get checkraised, doesn't mean he has the K (could be QQ, and he doesn't give you credit for the K.) If you do get a CR, slow down.

ScottieK