PokerStars No-Limit Hold'em, $1.00 BB (5 handed) FTR converter on zerodivide.cx

UTG ($77.85)
MP ($58.95)
Hero ($144.75)
SB ($116.95)
BB ($155.30)

Preflop: Hero is Button with 2, K.
1 fold, MP calls $1, Hero calls $1, SB completes, BB raises to $3, MP calls $2, Hero calls $2, SB folds.

Flop: ($10) K, 6, J (3 players)
BB checks, MP checks, Hero bets $7, BB calls $7, MP calls $7.

Turn: ($31) 5 (3 players)
BB checks, MP checks, Hero checks.

River: ($31) 7 (3 players)
BB bets $145.3 (All-In), MP folds, Hero ???

What would you do? My read is this guy is very laggy. What hand do you think would bet the river like this? I'll pretty much say I let the timer run out before I made my decision. I'll post the results once I get some responses.