i doubt he has a K, but i think it would be retarded to bet and not shove cause he has like 3/5 pb left on river. i cant remember stats cause poker ace is crapping out these days for me on 1 table, and just happened to be this table, but i know hes a fish, and to my memory, not a particularly aggro one. so im just not sure he calls with worse here, cause the board is so drawy, and some draws got completed.

PokerStars No-Limit Hold'em, $4 BB (6 handed) Poker-Stars Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

CO ($417.95)
Button ($586.25)
SB ($631.30)
Hero ($607.25)
UTG ($400)
MP ($279.35)

Preflop: Hero is BB with 4, T.
1 fold, MP calls $4, 3 folds, Hero checks.

Flop: ($10) 3, T, 4 (2 players)
Hero bets $8, MP raises to $16, Hero raises to $48, MP calls $32.

Turn: ($106) K (2 players)
Hero bets $80, MP calls $80.

River: ($266) 9 (2 players)
Hero bets $172, MP has about $150 left.