Opponent is quite loose, 37/19/8 over 94 hands, c-bets 70%.

When opponent checks this draw heavy flop, I expect it is usually to c/f or to c/c a marginal draw like maybe pair+oe or dry T98 type hand.

I like betting to just take it down and keep my range uncapped in future streets.

Complete blank on the turn and I continue betting for the same reasons as the flop bet.

He comes alive on the heart river but to me this is very odd as I would expect this player type to have bet all good flush draws on the flop.

Given no heart blockers in our hand we probably shouldn't be bluffing here, but I felt quite strongly about my read that he didn't have a strong flush here and pulled the trigger on the bluff raise.

So the hand he shows up with sort of falls in line with my flop read of his hand type (marginal made hand + marginal draw). However, his river bet surprised me as I don't think he can expect a large river lead to get called by worse more than it gets called by better, although admittedly he got max value from me here.