[highlife]

I fold the river. I assume villian has a mid Ace.

On the flop, he doesn't checkraise, since he views you as tight and that you will fold the turn with a medium pocket pair.

He also doesn't want to checkraise the turn because you will fold for the same reasons, and might even check behind. So he donk bets the turn, hoping you will call down. When you raise, he puts you on either KK or QQ or AK. If you have QQ or KK, you are raising for a free showdown of course, but he is not going to threebet still fearing AK, also if he does three bet, you will fold a worse hand.

On the river its obviously he is bet/folding, as he assumes you will make a crying call, and even possibly just call with AK.