Underfull faces a huge river bet

[ahnuld]

I dont think I'd call with AA but once you have one of the sets accounted for, hed, need some pretty specific hands to beat you here. He could also have something like 45 suited and he thinks he just bad beat your KK AA and is trying to get paid off when hes behind. I'd call the OP

[Chris Daddy Cool]

nothing you can do but call. theres a distinct chance he has you beat but of course theres the chance he has trips or has gone mad with AA or a pure missed draw bluff.