Interesting Hand

So I was playing in a 6max ring game next to a good aggressive player and I was sitting in the small blind with KK and action folded to me. I simply limped the small blind and the big blind opted to check. The flop was KQ2, all different suits, so I had pretty much all big hands locked up. My opponent, however was an aggressive player, especially when checked to, so I thought almost any check I'd make he'd bet back at me, but he didn't bet back, he opted to check. I immediately presume he probably has a Qx, some random ace high, or a random pocket pair 99-JJ and just wants to get to a cheap showdown.

So the turn comes an off suit 7 and so the board is still rainbow and I still have the nuts. I want to start building a pot, but I don't think he'll bet out at this point, so I bet like a third of the pot thinking he'd probably call with a Q. To my surprise, he reraises me for quite a bit. I start reconsidering my initial read and wonder if maybe he has Q7 or a set of 7's, possibly an AJ or J10 type hand turned bluff, but only Q7 and 77 made any sense to me. I felt like with a pair of 7's he'd bet out on the flop to see where he was at. I decide just to call. Even after my call, we're still pretty deep stacked.

On the river, another 7 peels off. This means quads are possible, but I thought Q7 was way more in his range here and there were way more remaining combinations of Q7 and only one combination of 77 remaining as well. My gut just told me he had 7's full of Qs and it was the only hand he'd play like this. And I sitting with 2nd nuts with my kings full. I really didn't want him to just flat my bet if I made a standard value bet and I also didn't want to give him a chance to get away if I bet 3bet him on the river.

I fake tank the river for a while. Purposely let my time bank go off for a few seconds and just open shove all in for like 3 times the pot. He snap calls. Sees my winning hand, then decides to show me his Q7.