villan is v tight. PT numbers are 14 / 1 / 5. Should i have folded to the 3 bet on the river? i was actually planning to fold but but changed my mind last second.

No Limit Holdem Ring game
Blinds: $2/$4
8 players


Stack sizes:
Hero: $406
UTG+1: $413.50
MP1: $400
MP2: $252.70
CO: $153.50
Button: $309.30
SB: $335.90
BB: $342

Pre-flop: (8 players) Hero is UTG with
Hero calls $4 (pot was $6), UTG+1 folds, MP1 calls, 3 folds, SB calls, BB checks.

Flop: ($16, 4 players)
SB checks, BB checks, Hero checks, MP1 checks.

Turn: ($16, 4 players)
SB bets $10, BB folds, Hero calls $10 (pot was $26), MP1 folds.

River: ($36, 2 players)
SB bets $25, Hero raises to $75, SB raises to $225, Hero calls $125 (pot was $311).

Results:
Final pot: $486

No, I wouldnt fold

that was pretty much what you were looking for so i dunno how you can fold it, but is very possible your beat

You got runner runnered to loose your stack.

At 14% VIP and only 1% raise, its more likely that he has a flush, AK or KQ than KT, K9 or K7. You an also beat 77

yeah KT is what he had. but i guess the possibility of 77, bluff, or a nut flush makes this into an easy call.