Villain is 12.5/8.75/0 at this point
Hero's table image is maybe a bit loose but aggressive

Would it have been too nitty to fold (should i have been able to get away from this) or is it just an inevitable losing situation (but a +EV line)?

I'm no expert so I can't just give you a yes/no answer, but let's think about ways to decide on this one.

How many hands do you have on villain? Is it a large enough sample to get a meaningful 3bet range? If it's a solid sample size and he's only opening 8-9% of hands, what do you think he's 3betting from the blinds, where he knows he'll have to play OOP for the rest of the hand? Top 2-3% (at most, IMO) seems like a reasonable guess. That's about AKs and 99+. Frankly, I don't think he's 3betting AKs and 99 from the SB if your sample is large enough to be meaningful.

Also, I assume the '0' you mentioned is his AF? If so he's playing pretty fit-or-fold post flop and pretty much never bluffing at a pot. That means his flop bet and turn raise are highly uncharacteristic, and deserve special attention. I'd take his overall range and weight it to the stronger end for sure.

So let's start from the top again, and be optimistic about our chances here. Let's say he's 3betting JJ+ and AKs pre-flop. Flop comes TK6 and he 3/4 pots it OOP. Considering this dude doesn't bluff and has zero aggression factor so far, I don't think he's scared of the king. That means QQ and JJ are unlikely, though not impossible, and I'd weigh his range toward AA, KK, and AKs (though like I said, AKs seems unlikely. I'd be unsurprised to see him 3betting pre with AKs).

So you beat two hands in his range on the flop, and are dominated by the third. When he check-raises you on the turn, that's tough. From a zero AF villain, I have to say, it seems like he's telling you he's got something.

If you have 500-1000+ hands on him, chances are he's taken a few big hands to showdown while you were watching. What post flop hands has he taken this line with, if he's ever taken this line? I'd say his chances of eagerly shoving all his chips in with over pairs and TPTK are pretty low, and flush draws aren't even in his range considering what type of villain he is. He has no two pairs or lower sets (hands that you beat) in his range, so there aren't any other options left if he's not check-raise shoving on the turn with TPTK or over pairs.

If you're multi tabling like crazy and playing auto-pilot poker, (which I do myself sometimes), then your line seems to be plus EV at the micros simply because villains in general are so loose and spewy, so you'll catch a ton
TPTKs, over pairs, lower sets, two pairs, and even skeptical pocket under pairs.

If you have time to closely pay attention to the lines a villain usually takes though, then IMO you can get away from this sometimes.

I'm just getting back into poker, but I'm working on a custom HUD that fits in a bit more information about a villain's common post-flop lines. Even if this guy was a stubborn continuation better on the flop, which a lot of people are with premium hands regardless of whether they hit the board, then I imagine it would be useful to see whether he quits after the flop, like most do.

I think the turn check-raise is your chance to get away from this if you have the info to see that it's totally uncharacteristic for a tight-passive player like this.

You can fold TT to the three bet but in a resteal spot, it's meh. You can take a flop and play in position.

After your hit your set I don't think you are ver getting away from it on this board. He has 6 value combos of AA, 3 combos of KK and 12 combos of AK not to mention the occasional KT or 66 or AQhh or JQhh or air. Even if we stick to the absolute top of his value range, AA, KK, AKs, we are still still crushing 75% of it.

Yeah that seems like a fair assessment too. Maybe you aren't getting away from it most of the time.

I still think that with certain tight/passive players it's fair to say they aren't 3betting AK OOP and then check-raise shoving on the turn. Of course it would very dependent on a specific read though.

This.

Bigger turn, rest of the hand is super standard and well played.

You can raise the flop to make it look like a draw.

typical micro nitfish line the villan doing check\shove OTT with KKK, obvious.
you could fold sometimes.... you having TT or low set its equal, or having KT lol, or having like Ace high lol.

i played a ton vs nits on fr on nl5 and im preety sure they just call AK on the blind LOL, and they cant valuebet that, they are preety bad, and im sure there are a ton of them that are bots.

rofl at ever folding here, ul wp

This is just a cooler, I'm raising flop though

Just lol no to folding.

its ok calling i guess, maybe almost breakeven. If we win 6 in 10 we pay the rake, or win 5 lost 5 we lose 1bi, but.. its okey i guess.

ofc we never win like 7 in 10, never.

maybe op should table select better and avoid playing low pairs and low sets against nits\bots. Steal them all day long and when they raise just fold all hands it doesnt matter trying to hit sets. The money comes just from steal.

There are more combos of AK and AA, than KK so this is fine.

Pre is fine too.

Yeah you should never fold on that flop to a nit who could easily have AA, AK. Plugging AA-KK AKS on an equity calculator in that spot vs his range and look how strong it is.

Seems well played to me, as stated earlier even the premium range you're putting him on loses 75% of the time to your set so raise flop and write it off as cooler.

1. bet turn bigger
2. calling 24/7