An underpair, against....?

[Nemesis]

When playing this hand I was a little confused, I had no real read on the villain. I felt that i was behind on the flop drawing to 2 outs, however his check on the turn made me think he was on middle pair with a flush draw possibly. Then when he bets into me again on the river I'm confused ...? What do you think he has, and please explain your logic.

Party Poker 1/2 Hold'em (6 max, 5 handed)

Preflop: Super Hero is UTG with Q/images/graemlins/heart.gif, Q/images/graemlins/club.gif.
<font color="CC3333">Super Hero raises</font>, MP calls, Button folds, SB calls, BB calls.

Flop: (8 SB) A/images/graemlins/diamond.gif, J/images/graemlins/diamond.gif, 2/images/graemlins/heart.gif <font color="blue">(4 players)</font>
SB checks, BB checks, <font color="CC3333">Super Hero bets</font>, MP calls, <font color="CC3333">SB raises</font>, BB folds, <font color="CC3333">Super Hero 3-bets</font>, MP calls, <font color="CC3333">SB caps</font>, Super Hero calls, MP calls.

Turn: (10 BB) 6/images/graemlins/club.gif <font color="blue">(3 players)</font>
SB checks, <font color="CC3333">Super Hero bets</font>, MP calls, SB calls.

River: (13 BB) 5/images/graemlins/club.gif <font color="blue">(3 players)</font>
<font color="CC3333">SB bets</font>, Super Hero calls, MP folds.

Final Pot: 15 BB
<font color="green">Main Pot: 15 BB, between SB and Super Hero.</font>

[purnell]

SB calls your raise, then check raises the flop. I'm thinking there is a good possibility of an ace with a weak kicker (as well as MP, FD, and maybe even a straight draw. Maybe I'm weak, but in this situation (QQ or KK with a flopped ace) I'm looking to get to the showdown as cheaply as possible. His check/call on the turn could indicate that he doesn't like his kicker after you played back at him on the flop, or that he is on a draw. When he bets out again on the end- who knows. Maybe it's a bluff with his missed draw, maybe he caught his second pair, maybe any number of things. Once the pot gets this big, you can't fold, I guess just make a crying call on the possibilty he is bluffing, but expect to lose this one. /images/graemlins/frown.gif
edit: forgot what i was going to add /images/graemlins/blush.gif

[imitation]

My typical reaction is A lower kicker and bets the river because its 1/2 at party and the player makes totally irrational plays. That or JJJ or possible even AJ this is against your typically passive player at 1/2 SH.

However I think there is enough maniac types and LAGs at 1/2 to bet the turn. Just for kicks I'm guessing he showed down 3d4d.

[Benjamin]

I think after the flop is capped, with a caller along for the ride, that you are against a pair of aces something like 95% of the time. I'd check behind on the turn, and probably pay off a non-diamond river bet since the pot is big.

B.

[Nemesis]

villain flips over A7o ... i lose.