I have a theory. It’s probably wrong, and the strongest piece of evidence is how the prophecy about the Demon King’s return is worded, (but that’s decent evidence in and of itself because the way these prophecies in media are worded is often very specific and literal yet also very vague,) but I have a theory. I think that there’s a possibility that Van, somehow, is/will be the Demon King mentioned in the prophecy. Ridicule me if you like, but I do have a fair amount of evidence (albeit it’s all circumstantial, but I do have evidence) for this theory.
Edit: My theory was completely wrong, never mind.