what Richter was thinking... [spoiler]
... when lying on the floor dying:
"Simeon, you unbelievable jack*ss!"
Or, in more detail:
"You're the only person I told about the Camerlengo's evil plan, you see me on the floor dying with everyone thinking he's the innocent victim, there's a bunch of guys around with guns who just used them to kill someone to protect him -- so you go and rush him just to get killed. Come ON!"