300/600 NL (6 max) - Holdem - 6 players

BTN: 15.36 BB (VPIP: 4.35, PFR: 4.35, 3Bet Preflop: 0.00, Hands: 46)
SB: 16.6 BB (VPIP: 10.53, PFR: 10.53, 3Bet Preflop: 12.50, Hands: 20)
BB: 28.78 BB (VPIP: 44.44, PFR: 28.89, 3Bet Preflop: 7.14, Hands: 46)
UTG: 46.94 BB (VPIP: 30.00, PFR: 10.00, 3Bet Preflop: 4.17, Hands: 51)
MP: 23.68 BB (VPIP: 9.09, PFR: 0.00, 3Bet Preflop: 0.00, Hands: 23)
Hero (CO): 70.05 BB

6 players post ante of 0.1 BB, SB posts SB 0.5 BB, BB posts BB 1 BB

Pre Flop: (pot: 2.1 BB) Hero has A 7

UTG calls 1 BB, fold, Hero calls 1 BB, fold, fold, BB checks

Flop: (4.1 BB, 3 players) 6 T Q
BB checks, UTG bets 2.05 BB, Hero calls 2.05 BB, fold

Turn: (8.2 BB, 2 players) 9
UTG bets 4.1 BB, Hero calls 4.1 BB

River: (16.4 BB, 2 players) J
UTG checks, Hero bets 14 BB

Random fish, did limp btn and bet 5x pot otf. But other than that nothing out of the ordinary, he has been playing passive.
Do you ever do this vs a reg?
What do you fold if you are him vs my bet size?
Thank you

iso pre

raise flop

fold turn

river is close but w/e

iso pre. like you line post. would expect fish to bet a straight so I'd expect a big bet to get folds often enough.