Check-raised w/ OESD and hit on a scary river ($4NL FR)

[rowhousepd]

I don't know if I played it well postflop and am going to go through it street-by-street. Villain is a reg (15/10/2.2) who chk-raises flop 8% and whose aggression tends to fade a lot from flop to river. No other reads.

Merge Network $0.02/$0.04 No Limit Hold'em - 7 players
CO: $3.31
BTN: $4.51
SB: $7.60
BB: $4.47
UTG: $1.60
Hero (UTG+1): $4.75
MP: $3.98

Pre Flop: ($0.06) Hero is UTG+1 with Q A
1 fold, Hero raises to $0.16, 1 fold, CO calls $0.16, 2 folds, BB calls $0.12

Flop: ($0.50) T J 9 (3 players)
BB checks, Hero bets $0.25, CO calls $0.25, BB raises to $0.75, Hero calls $0.50, CO folds

I might not normally call here, especially heads up, but it's not a huge raise and the pot odds are about 3.5:1. Plus if the CO calls the check-raise, the implied odds might make this well worth it. I also know BB is likely not to follow through on the turn or river w/o a monster. Is this thinking wrong? Am I making a loose call?

I'm thinking the villain's range here is { JJ-88, AJs-A9s, KTs+, QJs, AJo-A9o, KTo+, QJo }, in which case my equity is 35.1%.

Turn: ($2.25) 9 (2 players)
BB checks, Hero checks

I'm not too surprised that he checks, so do I check behind w/ the intention of folding the river if I don't hit and betting if checked to me? Or do I bet here thinking he'll fold 2 pair w/ this scary board or will fold a flush draw to a big enough bet?

River: ($2.25) K (2 players)
BB bets $1.50, Hero ....?

I hit my straight but this isn't a great river. Did the villain hit his flush? Or did he slowplay his trip 9's or a full house on the turn maybe? Is a call just spewy here?