KQ top pair +flush draw

I like checking behind turn, since many cards help you to improve and I hardly see any value from worse hands than KQo. Fold on turn raise is fine from my side since you do not know how clean your outs on straight and flush really are.

Not sure what you mean by villain being weak, I'm taking that as you mean he is fish and calling alot? On the turn Hero needs about 22% Equity to continue,

if we assume villain is check-raising with TPGK + we still have slightly above that, somewhere around the mid twenties depending on what you want to give or take out of villains range.I like a call on the turn.

If he flopped something strong like a set, two pair or even a straight, he'll likely be raising you on the flop. It looks like he either flopped the nuts and is now raising the turn for value, semi-bluffing with possibly an A♣, or just bluffing with complete air. QJ is also in his range still. I don't think it's wrong to fold, but I'd probably call and evaluate river.