25nl When should I be scared with KK?

[yntm3]

Ultimate Bet - No Limit Hold'em Cash Game - $0.10/$0.25 Blinds - 6 Players - (LegoPoker HH Converter)

SB: $10.17
BB: $23.64
Hero (UTG): $53.32
MP: $56.22
CO: $10.42
BTN: $23.40

Reads: <font color="blue">Villain is 25.8/15/3</font>

Preflop: Hero is dealt K[img]/images/graemlins/club.gif[/img] K[img]/images/graemlins/spade.gif[/img] (6 Players)
<font color="red">Hero raises to $0.85</font>, 3 folds, SB calls $0.75, BB calls $0.60

Flop: ($2.55) 6[img]/images/graemlins/club.gif[/img] 5[img]/images/graemlins/diamond.gif[/img] 3[img]/images/graemlins/club.gif[/img] (3 Players)
SB checks, BB checks, <font color="red">Hero bets $2.00</font>, SB folds, <font color="red">BB raises to $8.00</font>, hero?

Just a sanity check. Should I be stacking off every time here against this player? I could put him on an over pair between the board and KK a good percentage of the time but does this outweigh the times he holds 2-pair/sets?

Should I try and see a showdown cheaply, or try and get my stack in for max value?

Flame on.