What would you do here?

PokerStars - $0.02 NL - Holdem - 9 players

BTN: 38.5 BB (VPIP: 0.00, PFR: 0.00, 3Bet Preflop: 0.00, Hands: 2)
SB: 53 BB (VPIP: 20.41, PFR: 4.08, 3Bet Preflop: 0.00, Hands: 49)
Hero (BB): 261 BB
UTG: 104 BB (VPIP: 23.81, PFR: 23.81, 3Bet Preflop: 0.00, Hands: 21)
UTG+1: 147.5 BB (VPIP: 5.00, PFR: 5.00, 3Bet Preflop: 0.00, Hands: 20)
MP: 100 BB (VPIP: 28.57, PFR: 14.29, 3Bet Preflop: 0.00, Hands: 7)
MP+1: 113.5 BB (VPIP: 11.11, PFR: 0.00, 3Bet Preflop: 0.00, Hands: 9)
MP+2: 84.5 BB (VPIP: 50.00, PFR: 25.00, 3Bet Preflop: 0.00, Hands: 4)
CO: 48.5 BB (VPIP: 25.00, PFR: 25.00, 3Bet Preflop: 25.00, Hands: 4)

SB posts SB 0.5 BB, Hero posts BB 1 BB

Pre Flop: (pot: 1.5 BB) Hero has Q Q

fold, fold, fold, fold, fold, fold, BTN calls 1 BB, SB calls 0.5 BB, Hero raises to 4 BB, BTN calls 3 BB, SB calls 3 BB

Flop: (12 BB, 3 players) 3 5 6
SB bets 3 BB, Hero calls 3 BB, fold

Turn: (18 BB, 2 players) 2
SB bets 3 BB, Hero calls 3 BB

River: (24 BB, 2 players) 5
SB bets 23 BB, Hero calls 23 BB

SB shows K A (Flush, Ace High)
(Pre 43%, Flop 50%, Turn 99%)
Hero mucks Q Q (Flush, Queen High)
(Pre 57%, Flop 50%, Turn 1%)
SB wins 67.5 BB

You could look at this a could different ways, for me he bet sizing says a lot. The lead out on the flop for a weirdly small sizing looks like a blocking bet with a drawing hand. The turn bet is to test your interest level, once you call he's going to bomb the river. I see this a bunch, someone puts out a very small feeler on the turn then bombs the river with their value hoping someone thinks it looks just suspicious enough. You could also ask, why he would suddenly decide to bomb the river after the board pairs and you're so likely to have a flush? Trying to get to showdown with his set and then made a house possibly, now wants max value. But I'd fold, he's never bluffing here and you're behind all his value hands. He's never doing this with the J of diamonds so yeah.

Fold river. But raise flop.

How much would you raise on the flop?

To 14 or so at least.