Effective stack ~400.

Villain has $15 straddle UTG, it folds to me and I open raise to $40 w/ 88 in the CO, folds to Villain who calls. Flop comes A98, 3 hearts, Villain checks, I lead for 75 and he calls. Turn comes 5c, he checks again, I bet 180, he calls. River 3c, he now leads into me for the remaining ~105.

How do you interpret this hand? What went wrong? The fact that he check calls the turn and river makes me feel like he's drawing or is already nutted w/ KhXh. When the board doesn't pair and he leads the river I'm obviously not happy at all and I think I'm very rarely ahead, but don't think there's any scenario where I get out of this hand when I only need to be good 12.5% (18 combos of A9/A5 and maybe some ballsy missed flush jams?)

Smaller otf. Your bet is way too big and all it does is condense continuing ranges

Raise bigger pre, bet smaller otf and turn, both between 50-65% pot.

Obvious call now. People who 5x straddle are likely to show up with lolbad hands here.

Agree w/ every thing said here. Think you hit it on the head. I don't think want to get much bigger prep though, really just 45 or 50 IMO. Agree w/ 50-65% instead of the 85%-90% on flop and turn.

Exactly what he showed up with - 67o... Not sure how he can continue my flop bet of nearly pot on a 3 heart board here w/ an OESD, but definitely agree my sizing wasn't EV maximizing.

Easy game.

Just flop better flops.