Flopped set or value bet AA or A3....bluffs

I think this should be 4b pre and called off. For stack sizes

As played... Im leading flop with KK blocker

First of all, for me this is cold FPS 4-bet pre, this is super monster hand.
So, this is bet to cca $22 and if I get just called (not 5-bet to his/her AI which I call),
I lead FPS for opponent's AI. I agree with PermafLOat.
As played I would certainly lead with $6-$9, depending on Villain ( do I have any FE vs bad straits, if I do - I am betting even bigger to represent KQ having blockers).
Your delayed c-bet w/ blockers in unconvincing here, I would never fold my {(8,7),(Q,8)} in this hand OTT vs you, not mentioning that I don't fold any 2 pairs/sets now neither.
Your check OTR for me reveals your hand where you have OP and I could happily VB my (FH, any straight) vs your (AA,KK,QQ) and sometimes bluff my (JT,J9,9T, bare QQ as blockers) but for that move I need to know my Villain little bit better...

yeah 4b pre

donking wet flop like this (or almost any flop for that matter) HU leads to tricky job of constructing ranges, i would go for x/c on the flop and take it from there

^^ it's not a delayed cbet, his not the pf aggressor in 3way pot, it's a stab vs missed cbet...and i like it with the plan of barreling rivers too

Too many acronyms in these replies for my liking. Or as I like to say; tmafml

It certainly looks like a flopped set that feared the str8 or stubborn AA