Probably boring AK on monotone flop

[NLSoldier]

PokerStars No-Limit Hold'em, $4 BB (4 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: 2+2 Forums)

saw flop|<font color="#C00000">saw showdown</font>

<font color="#C00000">UTG ($344.10)</font>
<font color="#C00000">Hero ($681.75)</font>
SB ($384)
BB ($160)

Preflop: Hero is Button with K[img]/images/graemlins/diamond.gif[/img], A[img]/images/graemlins/spade.gif[/img].
UTG calls $4, <font color="#CC3333">Hero raises to $16</font>, <font color="#666666">2 folds</font>, UTG calls $12.

Flop: ($38) 5[img]/images/graemlins/club.gif[/img], 4[img]/images/graemlins/club.gif[/img], A[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
UTG checks, <font color="#CC3333">Hero bets $28</font>, <font color="#CC3333">UTG raises to $92</font>

My only read is that hes sitting with less than 100BB and just open limped in the CO.