Second nuts flush draw vs raise flop monocolor

PokerStars - €0.10 NL (6 max) - Holdem - 6 players

Hand converted by PokerTracker 4

CO: 54 BB (VPIP: 41.67, PFR: 25.00, 3Bet Preflop: 0.00, Hands: 13)

BTN: 66.3 BB (VPIP: 25.00, PFR: 25.00, 3Bet Preflop: 6.25, Hands: 68)

Hero (SB): 100 BB

BB: 101.5 BB (VPIP: 10.53, PFR: 5.26, 3Bet Preflop: 0.00, Hands: 19)

UTG: 144.9 BB (VPIP: 13.33, PFR: 9.33, 3Bet Preflop: 5.17, Hands: 153)

MP: 111.3 BB (VPIP: 23.08, PFR: 23.08, 3Bet Preflop: 0.00, Hands: 13)

Hero posts SB 0.5 BB, BB posts BB 1 BB

Pre Flop: (pot: 1.5 BB) Hero has K:spade: 7DIAMONd

fold, fold, fold, fold, Hero raises to 3.5 BB, BB calls 2.5 BB

Flop: (7 BB, 2 players) 9:spade: 5:spade: 4:spade:

Hero bets 4.3 BB, BB raises to 12 BB, hero???

Hero: Ks 7d

Flop: 9s 5s 4s

Es ev pagar el raise? Es que la mayoría de las manos que hacen raise ahí imo son As con gutshot, o back de escalera. Es un fold débil?