What is going on here?

[Carmine]

I don't know. With only the descriptions of Lag and Tag to go by it is hard for me to put MP2 on 77(I think he would tried to isolate a limper and a lag PF and would have raised the turn. Not to mention risking having it get checked through) or A7(again I think he isolates or folds PF. More likely folds with a 15% vpip. And would have raised the turn again).

On the other hand you have pretty much defined your hand between the flop and turn. Nonetheless, I think I call this on the river because MP2's play from CC preflop to the wierd play on all other streets just doesan't add up to me.