50 6max - straight on paired board

Villain's stats are 51/6/1.5 over 200 hands, and really tends to play his own cards without considering hand ranges for opponents. This leads to him betting on certain streets where its obvious his hand cannot be good. However, I have never seen him overbet ridiculously like this. On the flop I was relatively sure I could take it down there, and when I didn't I received a gift on the turn and a puke on the river. The push was out of character, and my initial reaction was to muck instantly, becuase this is exactly what I would do in his shoes with a boat. Who calls/folds? Anyone check behind on the river to begin with?

Party Poker No-Limit Hold'em, $ Hero (6 max, 5 handed) converter

Hero ($79.35)
UTG ($56.80)
MP ($71)
Button ($34.45)
SB ($51.13)

Preflop: Hero is BB with J, K. SB posts a blind of $0.25.
3 folds, SB (poster) raises to $0.75, Hero calls $0.50.

Flop: ($2) T, 5, Q (2 players)
SB bets $0.5, Hero raises to $2, SB calls $1.50.

Turn: ($6) A (2 players)
SB checks, Hero bets $3, SB calls $3.

River: ($12) A (2 players)
SB checks, Hero bets $8, SB raises $45.13 (All-In)

[DJ Sensei]

Bet more on turn. If the A helped him, you win a big pot. If it didnt help, well, you would have won a small pot anyhow.

On the river... I suspect he has Ax, and I call. I think he'd raise the turn if he had 2 pair, aces up. More often than not here: AK, AJ, A9, Ax... (especially if there was a flush draw out)