BB: $42.05
UTG: $54.90
Hero (CO): $63.85
BTN: $50.00
SB: $70.80
Pre Flop: ($0.75) Hero is CO with 8 
9
1 fold, Hero raises to $1.75, 2 folds, BB calls $1.25
Flop: ($3.75) 6 
3 7 (2 players)
BB checks, Hero bets $2.50, BB calls $2.50
Turn: ($8.75) T 
(2 players)
BB checks, Hero bets $6.50, BB calls $6.50
River: ($21.75) 6 (2 players)
BB bets $31.30 all in, Hero ???
Villain has 26/20 stats, we have no history. Never seen him before (prob not a reg)
Ugh, ugly spot. My first thought was "fold" cause I don't think he does it with overpair or A6 for instance. But now...if he has 2pair or set - why not protect from the vast amount of draws? Maybe he expects your range to be much more broadway-heavy. But still...if he had a set he'd want to protect and get more money in so he wouldn't have to shove for 1.5xPot on the river. So I think I'd call. If he had a set (full house, or even quads) he just played it perfectly vs my hand and is going to get my money I guess.
PS and the 6 does make full houses, but also makes it less likely he flopped a set. Does seem like TT, but still - raise for protection and value...
I´d snapcall that spot, since he can shove for value just 6x and he may also have there some kind of missed draw.
Also he would very likely c/r turn or flop 66/77/33/67
