Opp is a bad lag preflop, postflop he seems a bit passive, but I'm not sure. This is fine, right?

Party Poker No-Limit Hold'em, $ BB (6 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

Hero ($106.50)
CO ($45.50)
Button ($332.30)
SB ($71.40)
BB ($89.50)
UTG ($99.50)

Preflop: Hero is MP with K, K. SB posts a blind of $0.50.
1 fold, Hero raises to $4, 1 fold, Button calls $4, 2 folds.

Flop: ($9.50) 7, K, 6 (2 players)
Hero bets $8, Button calls $8.

Turn: ($25.50) A (2 players)
Hero checks, Button bets $9, Hero calls $9.

River: ($43.50) 5 (2 players)
Hero checks, Button bets $48.33, Hero folds.

Final Pot: $91.83