playing weak-tight at 3/6

[Tokyo!!]

Button is 17.5/8.8/2.94 over 434 hands. He seems very straightforward and has not got out of line. The guy in the middle is a loose/passive fish. Thoughts on flop/turn?

PokerStars No-Limit Hold'em, $6 BB (6 handed) internettexasholdem.com

CO ($672.90)
Button ($1428.85)
Hero ($640.05)
BB ($648.35)
UTG ($384.25)
MP ($591)

Preflop: Hero is SB with 3[img]/images/graemlins/heart.gif[/img], 5[img]/images/graemlins/heart.gif[/img].
UTG calls $6, <font color="#666666">2 folds</font>, Button calls $6, Hero completes, BB checks.

Flop: ($24) 6[img]/images/graemlins/heart.gif[/img], 4[img]/images/graemlins/spade.gif[/img], 7[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(4 players)</font>
<font color="#CC3333">Hero bets $15</font>, BB folds, UTG calls $15, <font color="#CC3333">Button raises to $84</font>, Hero calls $69, UTG folds.

Turn: ($207) 6[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, <font color="#CC3333">Button bets $132</font>, Hero folds.

Final Pot: $339