Wu'd you believe it

Colin Wu raises from mid position and is called by Kai Paulsen on the button. The flop comes Q Q K and Wu checks to Paulsen who bets 500, about 2/3rds the pot. Colin Wu thinks for a short while before calling. The turn brings Q and again it’s checked to Paulsen, who throws in a thousand chip declaring a bet of 800. Again Wu calls. The river is a meaningless 2 and now it’s quickly checked by both players. Wu turns over pocket 7s and the aggressor, Kai Paulsen, quickly mucks his hand.