I don’t think Lord English is going to die. The ouroboros and AURYN imagery implies a snake/two snakes that are consuming itself or each other eternally, but never actually completing the act.

Actually it’s just occurred to me that there’s also the Midgard Serpent, who encircles the world and bites his own tongue…and when he lets go the world will end. Which seems a bit like what Caliborn did, doesn’t it? Not all the way, but he broke the circle early. And then because of that, he reached the point where he could, and tries to, annihilate all of existence. I would love to explore this at greater length but I’m having trouble finding references to it in the Eddas and mythology books I have access to and I don’t want to be like, “Hey guys I read this thing on Wikipedia!”

Anyway, we know Calliope’s goal was a true union, rather than her overpowering Caliborn. Obvs a huge part of this has to do with how cherubs operate, which we don’t know entirely well. Assuming that Calliope will eventually have to face against Caliborn, the same way that her mother did with her father, and in fact all cherubs must do to mate (although obviously they won’t be mating, ew, gross, that’s also the only time cherubs directly interact so it’s our model), and assuming that she’ll be victorious, she’ll either have to kill him or bring about some kind of union, as she originally wanted to. I could see her killing him, for the good of everything, but it would be kind of boring, especially considering the rest of the story. Killing Lord English would leave the circle incomplete, like the one serpent we saw on either of the lollipop jujus.

We do know that one or another cherub’s spirit/soul/personality/whatever will die around reaching adulthood, but the point of Caliborn/Calliope is that they are different, so my guess is that they end up integrating fully into each other somehow, probably as a result of John’s new rule breaking time travel bullshit.