Missing value with KK?

[saxhoe]

Villain is 21/12/2.5 He has been pretty tricky after the flop, checkraising flop after a preflop raise and stuff.
Is this standard or do you just bet bet bet?

No Limit Holdem Ring game
Blinds: $0.50/$1
5 players
Converter

Stack sizes:
UTG: $137.42
CO: $90.50
Superhero: $147.22
SB: $130.18
BB: $227.32

Pre-flop: (5 players) Superhero is Button with K[img]/images/graemlins/heart.gif[/img] K[img]/images/graemlins/club.gif[/img]
2 folds, <font color="#cc0000">Superhero raises to $4</font>, SB folds, BB calls.

Flop: 8[img]/images/graemlins/spade.gif[/img] 6[img]/images/graemlins/club.gif[/img] J[img]/images/graemlins/club.gif[/img] ($8.5, 2 players)
BB checks, <font color="#cc0000">Superhero bets $7</font>, BB calls.

Turn: 7[img]/images/graemlins/club.gif[/img] ($22.5, 2 players)
BB checks, Superhero checks.

River: 4[img]/images/graemlins/club.gif[/img] ($22.5, 2 players)
<font color="#cc0000">BB bets $11</font>, Superhero calls.

Results:
Final pot: $44.5