UTG is a 12/8 reg, we've tangled a lot before and he's bluff raised me on the flop in the past. Here I think most of his range is PPs, so I don't know what he's betting into me with on the river when his hand clearly has SD value. I can't imagine that he has hit the flush here, I would not expect him to be limping SCs UTG. So can we call, or is this a set too much?

PokerStars No-Limit Hold'em, $0.50 BB (8 handed) Poker-Stars Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

SB ($61.60)
BB ($49.25)
UTG ($53.40)
UTG+1 ($49.35)
MP1 ($12.75)
MP2 ($30.65)
CO ($30.90)
Hero ($58.35)

Preflop: Hero is Button with 9, 9.
UTG calls $0.50, 4 folds, Hero raises to $2.5, 2 folds, UTG calls $2.

Flop: ($5.75) 5, 8, 2 (2 players)
UTG checks, Hero bets $4.5, UTG calls $4.50.

Turn: ($14.75) T (2 players)
UTG checks, Hero checks.

River: ($14.75) 5 (2 players)
UTG bets $12.5, Hero.....?