The Demon Prince goes to the Academy

Eleris did not look particularly pleased.

It was a plan to create an artificial dungeon that would swallow up countless adventurers in order to lure Cantus Magna, but she couldn't help but worry for those who would lose their lives in their pursuit of fortune.

It was strange that she had agreed to the plan that would inevitably lead to someone's death.

"If our business is finished, I shall take my leave."

"Please do."

Antirianus, Gallarush, and Luruien cast their teleportation spells and soon vacated the room.

Only Lucinil, Eleris, and I remained in the council chamber.

"Where's Lydia?"

"I told her to wait in her room."

I wondered if she was doing alright, spending so much time in such a cold and desolate place. Eleris seemed to be taking good care of her, but it almost felt like she was being raised like livestock.

Anyway, that wasn't the issue at hand.

"Alright. Lucinil and Eleris, come with me for a moment."

"Do you have more business to attend to?"

I nodded in response to the silver-haired girl's question.

"Let's go to the Demon King's Castle."

"The Demon King's Castle? That's... Oh, now that I think about it..."

"Right. It was said to be a hideout of sorts."

"Yes, we'll go there."

We needed to find a spell that could help with the fake dungeon construction and disguise. However, I was completely ignorant when it came to magic, so even if there were such spells at the Demon King's Castle, I wouldn't know. Moreover, the Order might question why we brought it up if it were already a well-known spell.

Thus, taking two archmage-level vampire lords with me should increase our chances of finding something useful.

------

I had informed Lucinil about the bunker, and Lucinil had relayed the information to Eleris, so they both knew about it. I wasn't sure if they had informed the other vampire lords, but I couldn't go to the Demon King's Castle bunker alone.

There were still garrison forces stationed there, and since I couldn't use magic, I wouldn't be able to avoid their gaze and reach the labyrinth located on the sixth underground floor.

However, with Lucinil and Eleris accompanying me, things would be different.

We arrived at the outskirts of the Demon King's Castle using a series of teleportation spells rather than warp gates.

"It's enormous."

Lucinil gaped at the sight of the majestic walls of the Demon King's Castle, visible even from a distance.

Despite the fact that it had eventually been conquered.

"Let's go."

Using various spells like invisibility and sound suppression, the three of us carefully made our way toward the Demon King's Castle, making sure to stay out of the garrison's sight.

"We don't necessarily need to find a dangerous spell. It doesn't have to be a dungeon trap or barrier. A spell that Cantus Magna would desire, something not too dangerous yet enticing enough to serve as bait, should suffice."

"Understood."

"Yes, Your Highness."

We would have to provide bait, just as the Black Order would. Regardless of the Black Order's true intentions, we would be allies until we found Cantus Magna and Akasha.

I knew I had to think about what would happen next, but for now, finding Akasha was my priority.

If I were a practitioner of magic, I might not have carelessly scattered those blood-like magical tomes, but I was an outsider when it came to magic.

Even though I knew they were valuable, I didn't feel guilty.

However, I couldn't take too many books. Charlotte might find out later that some books were missing. Of course, even if she found out, she wouldn't realize that I had taken them.

The garrison didn't detect us, and I took the lead since I knew the way.

The inside of the Demon King's castle was vast, so we moved for quite some time.

The garrison had already explored almost every part of the castle, except for the labyrinth. The commander had given up on investigating the labyrinth, and Charlotte hadn't pressed the issue.

The garrison would withdraw soon, having found nothing.

Eleris looked sad as she gazed upon the Demon King's castle.

She had always disliked war, but for some reason, she was the only one on the Council who had sworn loyalty to the Demon King. She had become a spy in the empire and then returned to the Demon King's castle.

I couldn't tell what Eleris was thinking.

"We need to go to the fifth basement level."

I knew where the entrance to the labyrinth was.

We walked diligently.

"There's no need for invisibility. There's no one here at all."

"Indeed."

Lucinil muttered in disbelief. Of course, that didn't mean we dispelled our invisibility and noise-canceling spells.

It seemed that due to Charlotte's lack of inquiry, Commander Alfred felt as if he had received a pardon.

So, the exploration had stopped entirely. The garrison was just loitering around the vicinity of the Demon King's castle, waiting to withdraw.

Soon, we reached the fifth basement level of the Demon King's castle, the breeding ground, and arrived at the entrance to the labyrinth.

"It's not that big?"

"Isn't it like that for all?"

"I didn't know such a place existed..."

"In the labyrinth, it seems the path only opens if there's an Archdemon."

At that time, I wasn't sure whether Charlotte had opened the path or I had. The only thing I knew was that the passage was connected to the labyrinth, but only if you were with an Archdemon.

Fortunately, the labyrinth guided me to the exit, even in my Reinhardt form.

As we descended the circular staircase, a long, straight corridor appeared, ending in a door.

At least I was sure that the labyrinth guided me correctly, regardless of my appearance.

But what if Charlotte came alone?

That part was still uncertain.

Eleris and Lucinil followed behind me.

With a creak, the door opened, and we arrived at the vast space I had previously reached with Charlotte and Saviolin Turner.

"Wow, what is all this?"

Upon arriving at the huge chamber, Lucinil widened her eyes and looked around.

Eleris, too, was bewildered as she looked at the passages and rooms.

"In the Demon King's castle... since when has there been such a place..."

Eleris mumbled blankly, looking around. There were supplies for living, bedrooms and kitchens, alchemy potions, and even a library. Lucinil and Eleris couldn't help but be astonished.

"It seems to have been built as a shelter... a space where no one but an Archdemon can enter..."

If I hadn't lost my memory, I would have come here.

It was still a headache to figure out what kind of impact Valier's survival had on the original story.

"Enough with the admiration. Let's search for the grimoires."

"Yes, Your Highness."

"Did I not say that we should look for grimoires that Cantus Magna would find tempting, or ones that would be useful in dungeons, like traps or barriers?"

"Yes."

"Alright."

Lucinil seemed to mull over my suggestions before heading into the library with Eleris to start searching.

I couldn't just stand idly by, so I began rummaging through the library's shelves.

"Wow... There's so much here."

"Indeed."

To be honest, this library was more than just a few shelves. There were enough books to rival a decent-sized library.

I wondered if all of them were grimoires, but there were also books for non-mages, such as those on swordsmanship and weapon techniques, scattered about.

"Hey, Archdemon."

I heard Lucinil calling me.

"Yes? What is it?"

"'What is it?' is informal."

"Yes, what is it?"

"Ugh, never mind. Anyway, you said you didn't know this place existed because you lost your memory?"

"Yes."

Lucinil's face appeared between the shelves, his cheeks puffed out in thought.

"So, if you hadn't lost your memory, you would've come here?"

"I suppose so?"

"Hmm..."

Lucinil tilted his head.

"Could the previous Demon Lord have survived if he had fled here?"

"Maybe."

This place was for Valier Junior, not for the previous Demon Lord. So, Valier didn't flee to the labyrinth but stayed in the Demon Lord's castle to fight against Ragan Artorius.

It didn't make sense for a ruler to flee when the allied forces were approaching the Demon Lord's castle.

Lucinil nodded, seemingly understanding this logic.

"Anyway, this place couldn't fulfill its purpose, since you couldn't enter in the end."

This bunker lost its purpose when I became Valier Junior.

And it wasn't until quite some time had passed that I finally discovered its existence.

Lucinil scanned the bookshelves, deep in thought. She picked up books, sometimes returning them or levitating them beside herself with psychokinesis. Eleris also browsed the shelves with a thoughtful expression.

I found a book on soul-manipulation magic in this place. I gave it to Charlotte immediately, but I couldn't help but wonder if it might also help Lucinil.

Could there be another book on soul-manipulation magic in this vast library that I didn't find before? Though this wasn't a real library, so it might not have extra copies of books. Still, I couldn't help but search.

Unable to find anything that met the conditions I had suggested, I was looking for other books on soul-manipulation magic in case they might be of any help to Lucinil.

"Hey, Archdemon."

"Why do you keep calling me? And stop calling me an Archdemon!"

"Alright, Valier."

"What for?"

Lucinil looks at me from across the bookshelf, with several books floating around her.

"Do you know what you're looking at? You're clueless about magic."

What's this now?

I was just trying to help.

But she didn't seem to be getting defensive; she genuinely seemed curious.

Maybe she's implying I should stop wasting energy on something I wouldn't understand and take a break instead.

Speaking of which, I'm somewhat curious about the taste of the preserved food here. It doesn't seem like I'll find the book I'm looking for, and my role is to open the path, not to find the book directly.

Just as I was thinking that,

[Introduction to Soul-binding Magic]

A book in an inconspicuous spot caught my eye.

There it was.

And I had a feeling I knew why there was another copy of the same book.

Though it was the same book, the language written on the title was different.

It was not the common language but the demon language.

It was the demon language version of the soul-binding magic book.

"Lucinil, have you ever heard of soul-binding magic?"

"Huh? Soul-binding magic?"

Holding the demon language introduction to soul-binding magic, I look at Lucinil.

"Just have a look at this for now."

Get ready to thank me, little one.

------

Unfortunately, I didn't receive any words of gratitude from Lucinil.

It wasn't because she couldn't read the demon language introduction.

"I already know this."

"…What?"

After skimming through the book, Lucinil said that.

"Soul-manipulating techniques may be taboo, but do you think I wouldn't know about this after living for so many years?"

Lucinil, who had wanted a soul, had likely done extensive research on soul-manipulation magic as well.

"This may not be a common magic book, but regrettably, it's magic I already know."

Lucinil gently runs her fingers over the cover of the Introduction to Soul-binding Magic.

Knowing the magic already meant that even with soul-binding magic, Lucinil couldn't achieve her secret desire.

"I could probably merge another's soul with mine, but I don't have a soul myself. That means I wouldn't be merging with another being; I'd be absorbed. That's why I couldn't try it."

The concept of merging different souls doesn't apply to Lucinil.

In the end, does that mean magic involving souls is useless for a being without a soul?

If so, what exactly is a soul?

I had never thought about it before, because I had one.

Only Lucinil, who didn't have a soul, desperately studied souls.

Lucinil looks at me and smiles subtly.

"Anyway, you thought of me, didn't you? I appreciate that."

"It's not like that."

"Oh, you're that kind of person. Fine. Cute."

Why is she being so annoyingly sweet?

In any case, it was Lucinil who had pondered the most about souls. After discovering a book about soul fusion, I wondered if it might be of help to Lucinil...

But the reality was quite the opposite.

Lucinil was the one who knew the most about soul-related magic, as she had spent a long time researching magic to obtain it.

So, the person with the highest probability of finding a solution to Charlotte's problem would be Lucinil.

"I have a question."

"What is it?"

Lucinil nodded, encouraging me to speak my mind.

"If there were a soul fused from two souls, could it be separated back into its original state, like before the fusion?"

Research on soul fusion was already underway.

However, Lucinil had already completed all the research. So, she must have known everything there was to know about soul fusion.

If the situation was urgent, Lucinil might be able to help Charlotte. Although, I would still have to think about how to explain it and what approach to take.

But then...

"Is that possible?"

With Lucinil's innocent response, all my hopes were shattered.

—---

Lucinil didn't know why I had asked that question.

But as if it was completely obvious, the response came back that it couldn't be done.

"You could mix two glasses of water into one cup and then pour it back into two glasses, but they wouldn't return to the original two glasses of water, right?"

"...Is that the concept?"

"It's a bit different in reality, but it's not much different from that."

It's impossible to return something that has already mixed and become one to its previous, separate state.

The image of Charlotte, overjoyed when she received the book about soul fusion, came to mind.

However, if Lucinil's words were true, even the research on soul fusion would not yield the results Charlotte desired.

Then what should I do?

If Charlotte's soul had already become inseparable from the Demon King's soul the moment they merged, would she have to live like this for the rest of her life? Waiting to be consumed by the Demon King's soul someday?

"Anyway, why are you curious about that?"

Should I tell her?

That the soul of the Demon King still lingers within the soul of the princess?

Lucinil might know what to do. If I tell her the truth, I might have to discuss what I want to do about it.

If it's possible, it's possible.

Even if it's not, it would be better to know for sure.

Now, I wanted to have something definitive.

"The previous Demon King fused a part of his soul into someone else's."

"...What?"

At my words, Lucinil's mouth hung open, as if she had heard an unbelievable story.

"No... Did he really do such a thing?"

"The circumstances make it quite certain."

"So, even after detaching part of his soul and implanting it into someone else... he was still fine?"

"I'm not quite sure about that, but..."

Lucinil thought that what the Demon King had done to Charlotte was terrible, but it seemed as if she perceived it in the exact opposite way.

The insane act of splitting one's own soul was already an awful thing to do to oneself.

"Is it hard to bear a fragmented soul?"

"It's not just about being difficult to handle; it's a miracle that one doesn't go mad. I might not have been able to maintain my sanity… What kind of person was the previous Demon King?"

It is unknown whether the predecessor Valier had gone insane. However, considering the way the Demonic War unfolded, it seemed that he was not completely consumed by madness or had lost his senses.

Planting his soul in Charlotte must have been a huge risk for the Demon King as well.

And so, at that time.

It was understandable that the Demon King's soul, which had been corroding Charlotte's body, was on the verge of being lost. He didn't recognize me, and he just seemed to be mad.

The Demon King had somehow managed to keep his sanity, but the soul that had mixed with Charlotte could not maintain its identity, could it?

After hearing my story, Lucinil was dumbfounded.

"So… he knew he would lose in the Demonic War… and prepared in advance for some kind of resurrection. I don't know if that's even possible…"

Lucinil seemed to think that what the Demon King had attempted was too dangerous.

"Do you want to fully resurrect the soul of that Demon King?"

I shook my head in response to Lucinil's question.

"No. I want to get rid of it."

"…?"

What a brat, huh?

Lucinil looked at me with that kind of expression.