it's actually one of the best possible flops for sb I think, as his range should interact with QJ really well so I wouldnt go crazy with cbets on this board but multiway I think you just have to cbet to thin the field with KK, I think you played this hand fine, not too happy calling the river but I think price is just slightly too good

Getting roughly 5:1 on a call here makes this a pretty easy call mathematically, but I wouldn't love it. I see JJ or 66 here alot, but that's only 6 combos total. I would also expect villain to play QJs this way, and potentially AQ at least some of the time.Those are hands I would consider villain's value range, as I would expect to see a 4b from QQ most of the time.
However, If you assume villain doesn't 4b QQ ever, he has 9 combos of boats (66,JJ, QQ), and 4 combos of QJs. If villain only value bets with these hands and never bluffs, you are still getting the right price to call. In reality villain is probably playing AQ like this some of the time and probably has a couple bluffs, so this is a fine call.

river
As mentioned above easy call on the river because there are enough combos that are bet on these levels that you beat (AQ and QJs).
flop
But I would bet a bit bigger on the flop (1/2 pot) as both AQ and AJ prob will call on a decent flop bet and I would be eager to build a pot here and let draws such as KT, TJ and AK and AT pay to see a card.
Anyway you bet 1/3 pot and get min-raised in a multi-way pot which makes that all alarms should go off but folding KK is out of the question even a loose passive player might play AQ this way and there 12 combos of AQ.
turn
He bets again on the turn now you have to decide if you want to play for your whole stack if he bets again on the river the odds will just be to good. Think the turn is the critical decision here will you be good enough off the time? If villain is capable of taking this line with AQ then surely your getting the correct odds even if you have to call off on the river. You describe the villain as loose-passive and I don't believe this type of player will do this enough with AQ so the turn is a fold in my opinion.

I think the key point is, if he is capable of value betting AQ on the flop. Because his bluffing frequency in this line is ofc really low.
If our answer is yes, then the sizings on the later streets are kinda good for us, cause they are representing some thin value which AQ definitely is. So if you feel like he can be value betting AQ on the flop, then you probably have to call it down against those sizings.

However against loose-passive players I would be really careful if they start doing things like this. You know, he just cold call 3bet and raise your cbet with one player behind. Some voice is telling me, that he is not going to play AQ this way 100% of the time.

That being said the nitty fold on the flop is not as bad as it might looks like. Imo it isnt huge -EV and keep in mind, that with this tight fold you can avoid a tough decisions and crying calls on the later streets which may makes you even more tilty... (since you will be losing more often than winning) which might be in the summary much -EV than the fold itself.

Yeah kind of gross spot but I cant find a fold, esp on this river. How loose passive is he?

Why would he bet river so small, what does he has left after his river bet? 10$ ?
Or is this bet sizing more common on 50nl stakes?