25NL - 55 flops a set, yay?

[Willem]

MP is a 41/7/0.5 over a small sample.
CO is a 20/14/2.4 over a small sample.

I had no reads on MP. I had played one hand against CO where I stacked him because he called all the way with tptk.

PokerStars No-Limit Hold'em, $0.25 BB (6 handed) pokerhand.org hand converter

BB ($25.25)
UTG ($26.95)
MP ($25.70)
CO ($44.10)
Hero ($83.25)
SB ($12.50)

Preflop: Hero is Button with 5[img]/images/graemlins/diamond.gif[/img], 5[img]/images/graemlins/heart.gif[/img].
<font color="#666666">1 fold</font>, <font color="#CC3333">MP raises to $0.75</font>, <font color="#CC3333">CO raises to $2.5</font>, Hero calls $2.50, <font color="#666666">2 folds</font>, <font color="#CC3333">MP raises to $5</font>, CO calls $2.50, Hero calls $2.50.

Flop: ($15.35) T[img]/images/graemlins/heart.gif[/img], 5[img]/images/graemlins/spade.gif[/img], K[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(3 players)</font>
<font color="#CC3333">MP bets $20.7 (All-In)</font>, <font color="#CC3333">CO raises to $39.1</font>, Hero ...?

What do we do here?

Let's assume it would be right to fold here, if this is so, shouldn't we fold this hand pf?

I think a strong case could be made for folding this hand to CO's raise pf, because MP is still to act, but I'm not sure.