[MLG]

I'm not sure why you checked the turn here. When he calls the flop, I think its much more likely he has a draw of some sort (and not necessarily a good one) than a marginal made hand. This turn check gets more money in against a marginal made hand at the expense of giving free cards to draws. I'd almost always lead the turn.

After you checked and he bet I'd be leaning away from marginal made hands and to big made hands/combo hands. A set is certainly possible, but hands like K10 of hearts or J10 of hearts are also fairly likely i think. Another KQ is also quite possible. No way to fold. So yeah, if he has 77/66 so be it.