"Charles," Erik says, firmly but sympathetically. "I need to tell you something. There are more of us out there," he says. "There are universes where we meet as teenagers. Universes where I die in the place of my children. You have to understand that we are not unique, we almost seem to be a constant."

And then, he smiles. "I think, in all of the universes so far, that we were friends." Once, anyway. He seems to fight Charles most of the time.