Jaime is standing vigil over his ever-smellier father's corpse. Presumably this is some sort of unfathomable Westerosi tradition. He's wracked with guilt that he caused all this by freeing Tyrion. Actually he caused all this by picking the absolute worst time to tell Tyrion the truth about his first wife. He's also consumed with jealousy at the idea that Cersei would sleep with Lancel and a Kettleblack, as Tyrion told him.
Varys has done a runner. He didn't want to free Tyrion in the first place but Jaime would have killed him otherwise.
Cersei comes to beg him to be hand but goes off in a huff when he says no. But later he helps her out a bit by explaining how to deal with Mace Tyrell, by sending him off to capture Storm's End. It seems like Jaime could just help Cersei out like this from time to time without having any official capacity. She still needs to choose a hand, though.
