AA on the button

[papawawa]

CO seems like a LAG. I'm not sure what you think he had that could beat your aces (KK, QT, KJ, K9, JJ, 99 or J9). Most LAGs would either raise KK preflop, or if he's tricky, check re-raise so he probably doesn't have top set. Many LAGs will cap TPGK, so I'm thinking KQ, AK, KT, but the aforementioned hands are a real possibility. However, you can't gain information by merely calling one bet. A raise on the turn is definetly a good move. If he re-raises, you're probably beat, but have to call down. However, when you hit your set on the river, you can eliminate many hands that could beat you, leaving only QT. This is really only hand you have to worry about on the river; there's hardly a chance he rivered a flush. Even if you think he's got it, you still have to call hime down. A raise might be in order if you don't think so.