I don't know your read on Villian prior to the hand, but I'd raise the flop. A lot of people are pushing preflop in cash games to re-raises with AK and you have 2 Kings. AQ and maybe AJ would be the only hands I'd see beating me here. Can he laydown AT-A7 preflop? This is important for the basic in the moment number guesstimations. The $9 on the flop is a flush draw, lower pair, or a weak lead with a monster.

The monster's pushing to your re-raise. A lower pair will fold to a min raise. The hearts are what can make this expensive and a heart's only hitting the turn ~20% of the time. With $37.50 in the pot, make him call another $15 by raising it to $24. You'll take down the $37.50, he'll push to protect against the hearts with a monster, or he'll call with hearts. In that case, you can bet $40 or push a non-heart. If he elects to just call with AJ on the flop, he could fold this on many turns. This all assumes that he checks the turn, of course AND that he's not slowplaying a set of 9's or A9 which along with AQ are the hands I see him pumping the flop after you raise. In the case a heart hits, he won't bet the turn or river with anything you can beat if he did call you on the flop with Queens or Jacks (which we're saying that he won't do.).

Calling the flop as you did isn't a bad option, but only if that river card price gets bumped up to around $30. I'd say that you were lucky that Villian didn't exploit your obv weakness, though and his turn bet many times makes your $9 call on the flop dead money with the best hand many times. But if you'd seen this stuff from him already, then you played it fine. If he has a shitty Ace, he'll play it like QQ-TT and only bet bigger with something you have beat.

The heart hits the river and he only bets $9. Again, lucky you, unless this was his M.O. as I stated earlier. It would suck if he bet $20-$25. That'd make raising the flop to $24 not seem so out of line.

I'm just laying out your options as I see them. Personally, I'd raise this flop, but use my knowledge on Villian. Even with no flush draw, I'd raise. If I get cold-called, we'll get a cheap showdown because of our position. In $100-$1000 games, people aren't laying down KQs, KJs, JTs, QJs, etc. This isn't a "stake level thing." People are just stupid.

EDIT: Just read the results. Oh my God! I hope you made a note.

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