KK could be up against Aces?

[PhatPots]

Party Poker No-Limit Hold'em, $ BB (5 handed)

BB is a TAG with 19/13/1.69 over about 250 hands

Button ($390.95)
SB ($359.75)
BB ($512.30)
Hero ($278.60)
MP ($455.35)

Preflop: Hero is UTG with K [img]/images/graemlins/heart.gif[/img]K [img]/images/graemlins/diamond.gif[/img]
Hero raises to $8, 2 folds, SB (poster) calls $7, BB raises to $27, Hero raises to $65, SB folds, BB calls $36.

Flop: ($138) 6, 5, 4 (2 players)
BB checks, Hero bets 55, BB raises all-in.....Hero?


What else could the BB have to make this play? Thoughts

Final Pot: $138