Rivered str8 facing check/push on scary board

Villain is fishy but I haven't seen him donk off his stack and haven't seen any outrageous bluffs. Stats are 33/5/3 over 900+ hands.

Full Tilt Poker - No Limit Holdem Ring game - Blinds: $1/$2 - 9 players - Converter

Stack sizes:
UTG: $192.60
UTG+1: $179
Hero: $229.55
MP2: $313.70
MP3: $192
CO: $81.85
Button: $501.75
SB: $139.60
BB: $103.75

Pre-flop: (9 players) Hero is MP1 with K:heart: Q:diamond:
UTG calls, UTG+1 folds, Hero raises to $9, 6 folds, UTG calls.

Flop: J:spade: T:spade: 5:spade: ($21, 2 players)
UTG checks, Hero checks.

Turn: T:club: ($21, 2 players)
UTG checks, Hero checks.

River: A:club: ($21, 2 players)
UTG checks, Hero bets $15, UTG raises all-in $183.6, Hero...

tripple check with the flush and then push all in when the board pairs, i dont buy it either he hit a full boat on the river or he interpreted your bet as a total steal and was looking to school you, do you have any reads on him? Known to be an ultra aggressor with total disregard to money or is he a supertight passive player?
In this case i would say call 25% fold 75%...

I fold here against this massive raise. If Villain bluffed me out of this pot. So be it. Those who get to run away get to live another day.