400NL 88 overpair facing weird line from pf raiser

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PokerStars No-Limit Hold'em, $4 BB (5 handed) pokerhand.org hand converter

Button ($394)
SB ($845.45)
Hero ($381.60)
UTG ($477.40)
MP ($119.90)

Preflop: Hero is BB with 8[img]/images/graemlins/heart.gif[/img], 8[img]/images/graemlins/spade.gif[/img].
<font color="#CC3333">UTG raises to $14</font>, <font color="#666666">1 fold</font>, Button calls $14, <font color="#666666">1 fold</font>, Hero calls $10.

Flop: ($44) 2[img]/images/graemlins/diamond.gif[/img], 6[img]/images/graemlins/spade.gif[/img], 2[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(3 players)</font>
Hero checks, UTG checks, Button checks.

Turn: ($44) 3[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(3 players)</font>
Hero checks, UTG checks, <font color="#CC3333">Button bets $28</font>, Hero calls $28, <font color="#CC3333">UTG raises to $92</font>, Button folds, Hero is confused?

i normally just bet the turn but thought it would be more likely that someone takes a stab at the pot than for them to call a bet. no real reads but he seems decent in the ~30ish hands he's played so far. what the hell does he have?