K9 from BB $25NL

[prk]

$25NL on Pary 6max. Hero is BB with $56. UTG makes it $1 to go. 2 callers. Hero calls $0.75 with K [img]/images/graemlins/diamond.gif[/img] 9 [img]/images/graemlins/diamond.gif[/img]

Pot = $4.25
Flop K [img]/images/graemlins/spade.gif[/img] 4 [img]/images/graemlins/diamond.gif[/img] 6 [img]/images/graemlins/diamond.gif[/img]

Hero bets $2.5. UTG folds, EP1 folds, Button pushes $46. (Button is a maniac who sat down about 10min ago, lost a buy-in, reloaded, got down to $10, and sucked out on a few people with crap cards to get up to $47)

What is Hero's play here??? Easy call or fold?