William found that even though Lorelei wasn’t particularly talented in the area of ki cultivation, she did have knowledge about it. William surmised that was because she liked to know everything. That said, William had a few questions he thought she might be able to answer. “Where does ki come from?”

“Well, it’s cultivated in the soul, so I suppose it comes from there.”

“Yes, but how does it get there?”

“It’s just born there, isn’t it?”

“But what about conservation of energy? It has to come from somewhere.”

Lorelei nodded. “That’s true. It doesn’t come from any surrounding energy, at least not such as we can detect. It certainly isn’t mana, as that would be very easy to tell.”

“For you, anyway.”

Lorelei ignored William’s interjection. “The world is vast. Perhaps there is indeed a source somewhere, or nowhere, since if it were truly in a particular place it would be less efficient in certain locations. On the other hand, if the source is far enough away, even just the distance of the sun, there wouldn’t be any noticeable difference in efficiency from anywhere. This assumes that the energy source isn’t blocked by matter, which it doesn’t seem to be. Assuming it even has a location.” Lorelei paused to take a breath and think for a few moments. “Other theories include that the energy is evenly distributed everywhere, or that it indeed doesn’t have a location. This is when people even bother to make theories, of course, instead of just accepting it. With some of these, it is entirely possible that one day… it will just run out. No more ki. This seems unlikely, but with no way to determine the source or exact magnitude of it, it is hard to say.”

“So, which theory do you believe?”

Lorelei shrugged. “I’m not sure. However, there are more theories connecting it to reincarnation. Cultivation is definitely connected to the soul. It is just that reincarnation is so hard to study. In fact, it is only assumed that everyone reincarnates with memory loss and their cultivation erased, when in fact they could be digested into some larger conglomeration of souls, then be remade as just part of the materials for a new soul. However, there is decent evidence that most or all souls are probably kept separate, though either result is speculation.” Lorelei paced back and forth as she was talking, emphasizing certain points with her hands. William listened intently. Though he’d heard some of what she was saying before, it was fun to watch her enthusiasm as she spouted on like a professor. “Of course, there is another problem. Populations increase. Not just of humans or… demons, but of animals, insects, and the like. Perhaps there are a certain number of souls available, of their various types, and once that limit is reached things will stop being born.”

“...but you don’t believe that.”

“You’re correct, I don’t. Souls seem to be tied to life, and life to souls. I imagine new souls are born as new life is born, though not at exactly the same time or the same rate. After all, old souls are reused. Though, I will admit that my reasoning for this is based more on intuition than any kind of proof in either direction.”

William nodded. He actually had a good reason to believe the same. After all, why else would he come from another world? Simply put, an unexpected lack of souls. Then, for some reason, the universe that Earth was in shared some souls with this one. William didn’t believe Earth was in the same universe as where he was now. After all there was magic here. In theory, it would be possible for there to be nothing that interacted with magic on Earth, or no mana, but there were other rules that were different as well. For example, ki cultivation and body training. There were limits on how far human bodies could go where he came from. Here, those limits just slowed down progression, and with the right methods they were merely suggestions. William supposed that the genetics of humans here were different from those on Earth, but the fact that they looked the same yet would be so different was a bit much. On the other hand, William wasn’t sure why there were humans here at all. Going back to ki cultivation, William doubted that it would be undiscovered or kept a complete secret. Surely someone would have wanted to show the world what they could do. Though, William supposed that if there really were an energy source for ki somewhere around the distance of the sun here, and Earth’s sun didn’t have one, that would render that impossible. However, William felt that it would actually be easier to explain as it being a different universe than somehow just lacking all of those traits. “So, how does that connect cultivation and reincarnation?”

“Ah yes, well… there is one theory that the world is alive, and gains energy from that life, then fostering the growth of that life with mana and ki. Not that there seems to be any particular thought involved, if that is the case. It would only be ‘alive’ in a vaguely related sense to what we normally think of as life. However, that would allow for the power to come from all life, though only a small bit from each individual creature. Of course, if each creature could use magic or cultivate ki, there would not be enough energy available. Thus, a mass extinction of life would theoretically result in less available energy, though of course this has never been tested for obvious reasons. It’s impractical.”

“Also immoral.”

“Well, yes, that too.” Lorelei stroked her chin. “Oh yes, on a somewhat related note… what is this?” She started writing something. It wasn’t in the language of Ostana, nor of Liaoyang, Eclea, or Ustil. William didn’t know the demon language, but he also knew this wasn’t it. That was because it was in English. It was a faithful representation of what was written on the poster William had used to try to find people reincarnated from Earth.

“That? That’s a secret code language I made up.”

Lorelei nodded. “See, I would believe you. After all, that is a reasonable thing to do. I know you did use it to keep your notes secret… but there’s more.” Lorelei continued to reproduce the rest of the poster, with its text in Ostanan asking if people knew or recognized the language, and the reward if they could prove that to William. “See, why would you ask if anyone knows a language that you made up? They couldn’t possibly know it. That’s the whole point. So then… what is it?”

William sighed. Of course Lorelei was the type to find such details and then remember them for 150 years. She even had remarkably good penmanship in a script she didn’t know. Now that it was brought up, William wondered why she hadn’t confronted him about it in his previous life… and then he remembered the current context. Explaining things was going to be tricky, at best. Of course, William could just tell her the full truth, but in this case William wasn’t sure whether to trust her with it. He could just tell her that it was a secret, but that often just lead to her wanting to know even more. It wasn’t that William wouldn’t love to hear her questions about another world, but rather that he didn’t trust that she wouldn’t be too interested. Right now, she was interested in destroying the Demon King, and thus was working with humans, but William knew she wasn’t exactly a saint. Though she hadn’t actually done anything to make him have such feelings, William still didn’t entirely trust her.