This river felt standard, but w/e

[SNOWBALL]

Hollywood park 15/30

Loose and mostly passive player limps UTG. I raise KQo in the SB, and this 300 year old asian guy who I have never won a hand against folds.

HU to flop of ATJ 2 spades.

I lead, and UTG thinks about it for a little while before calling. I'm not sure what this means except I don't think he has a flush draw, but I really can't figure out what else it means at all.

Turn is a 7 of spades. I have no spade. I lead. He calls quicker this time, but not super quick.

River is a K. I bet. He raises. Your action and thought process throughout the hand?

A note about the player: He is mostly passive, but I have seen him be aggressive in really weird and bad spots, so it's like he has a random switch in him or something. 9/10 he just checkcalls top pair no kicker vs PFR, then the tenth time he leads every street with bottom pair.