Imperial Arcane Library, Emperatos Magic Department.

The sheer volume of magical research materials stored in the Magic Department was so vast that one could wonder if a lifetime would be enough to read them all.

And that was just for the field of dimensional magic alone.

However, having access to the royal magic department's archives was not just about being able to peruse the precious tomes stored within the library.

One could also summon professional magicians who had already fully understood and internalized these books, to assist in comprehending the content, and receive expert help to provide specific research materials for abstract inquiries.

It was as if Harriet was studying like an emperor.

"Imaginary dimensions?"

"Yes, Your Highness."

And so, Harriet was reminded once again, after a long time, that she was indeed a noble, and quite a high-ranking one at that.

While at the academy, she had been scolded and reprimanded by a rascal from a poor background, but she was originally of such a lofty position. The highly esteemed royal magicians, who held positions of great authority and power, would address her as "Your Highness" and would carefully share their knowledge, anxious not to offend her.

Of course, it would be different if the rascal were not there.

Among her classmates were the Crown Prince, Princess, and even a prince from the Kernstadt royal family.

Though it was against school rules to use one's rank to suppress others, there were still classmates of similar or higher status.

Thus,

Harriet was happily studying, her noble pride swelling after a long time.

At the mention of the term, Harriet tilted her head.

Imaginary dimensions.

It was the answer she received when she asked for an explanation about the incomprehensible part while learning about the warp gate system.

"In other words, it refers to a dimension that is assumed to exist, even though it doesn't actually exist."

"Uh-huh... So, we're assuming it exists even though it doesn't?"

"Yes."

"Why do we need such a concept?"

At Harriet's question, the research magician began to explain slowly.

"Bidirectional one-time-use dimensional gates do not require such a concept. Once activated, they close after a certain period. However, the warp gate system is a shared network of permanent multi-directional dimensional gates."

To simplify the understanding, the researcher drew a diagram on a piece of paper placed on the table.

[Gate - Gate]

"With such a structure, it's more convenient to create it as a one-time-use gate. There's no need to set up the concept of an imaginary dimension. Setting aside the complexity of the magic itself, isn't the structure quite simple? There's only one connection between the gates."

"I suppose so."

"But if there are three gates, how many total connection paths would there be between them?"

"Three, right?"

Suppose there are three gates: Gate A, Gate B, and Gate C. The connections between each gate would be A-B, A-C, and B-C, making a total of three connections. Since the connections are bidirectional, the order of the gates doesn't matter.

"What if there were four gates?"

"Then there would be six connections."

And so on.

"As the number of warp gates increases, won't the number of paths increase exponentially?"

"Yes, that's correct."

"It's not that every warp gate is connected in this way, but the number of connections between gates already exceeds two hundred thousand."

"…That's an incredibly large number."

Hearing the researcher's words, Harriet couldn't help but be taken aback. She hadn't known the extent of the connections between the warp gates.

"The warp gate system is the largest magical system in the history of the continent. Therefore, a common space perception system was needed to determine which path to set for the permanent dimensional gates and which gates to connect. That's why we created a virtual map called the Imaginary Dimension."

A virtual map.

If you created a dimensional gate on your own, there would be no need to share it with anyone. It would be a one-time magic based on your own thoughts.

However, the warp gate system is no different than a collaborative architecture created through the cooperation and collaboration of many magicians.

Everyone needs to have the same map or blueprint in their heads in order to add or modify something in the warp gate system, and that is what's called the Imaginary Dimension.

The understanding of the virtual map or blueprint of the Imaginary Dimension that researchers have accumulated so far.

A virtual dimension that is assumed to exist but does not actually exist.

An understanding of it is necessary to access the magic of the warp gates.

"This is the most recent map of the Imaginary Dimension."

The researcher unfolded a huge flat map in front of Harriet, which covered the entire table and more.

It wasn't just a simple drawing of dots and lines.

The map was filled with complex strings of characters, detailing each dimensional gate, their connections, properties, as well as the blocking properties, usefulness, and connection strength.

Although it was a map of something that did not exist, this map changed the course of human history.

Harriet suddenly wondered.

Another world.

What exactly is another world?

The researcher said directly that the Imaginary Dimension is a non-existent dimension.

"…So, this isn't an actual existing dimension?"

It's just a virtual concept created to help the common understanding of future magicians and modern researchers, and should ultimately be understood as a blueprint.

"Yes, that's why it's called the Imaginary Dimension."

The researcher nodded at Harriet's words, as if it was obvious.

"However, nowadays, some argue that we cannot definitively say that the Imaginary Dimension does not exist."

"…What do you mean?"

"Dimensional gates are ultimately magic that connects space to space directly. The basic principle does not change even if there are hundreds of dimensional gates."

Harriet understood this as well.

"But isn't there an intermediate space that's skipped over when connecting the dimensional gates?"

"Intermediate space...?"

"We use the gates, but the gate itself doesn't exist at either the entrance or the exit. It's treated as a phenomenon."

The researcher pondered, resting his chin on his arm.

"However, the gates can only be passed through; we can't touch or reach the gates themselves. We can control and manipulate them, but it's unclear whether the phenomenon of the gates belongs to our reality or something else. Some say that warp gates don't actually skip over space, but rather pass through some sort of intermediary area within the space, and that this area is a real space according to certain magicians."

"Hmm..."

Warp gates.

Traversing them shortens the space, but the gates themselves are a peculiar phenomenon that can't be touched or reached at either the entrance or the exit.

One can use gate magic, but what exactly is the nature or phenomenon of the gates?

Is the intermediary area passed through when using warp gates a real space or not?

It was clear that this issue had not been definitively resolved.

"Some argue that imaginary dimensions have actually emerged due to the distortion of the dimensional concept caused by the constant operation of warp gates leading to system saturation, but these are just speculations."

The researcher gazed intently at the map of the imaginary dimension.

"The important thing is that the warp gate system has spread far too rapidly due to its convenience. This large-scale magic hasn't been properly tested for potential dangers."

As Harriet had previously sensed.

The warp gate system is a very dangerous magic, but its convenience allowed it to spread rapidly without proper risk assessment.

That's why, even now, with the long history of warp gates, magicians have varying opinions on them.

No one could predict what form the catastrophe they might bring would take, making the situation even more uncertain.

Furthermore.

Harriet looked at the vast virtual map in front of her with a sense of dread.

"This map of the imaginary dimension... Not just anyone can see this, right?"

"Of course."

The researcher spoke quietly.

"Without the royal family's permission, even if you desired it, Your Highness, you wouldn't have been able to see it."

Although she appeared nonchalant, Harriet was looking at one of the empire's most crucial secrets.

Understanding the imaginary dimension would enable one to interfere with the warp gate system.

Soon.

It's possible to use it for ill purposes if one so desires. That's why, if Harriet understands the map of the imaginary dimension and comprehends the warp gate system completely, it means that Harriet can tamper with the warp gate system as she pleases if she has bad intentions.

"Do you think... it's just my imagination... that the warp gate is too dangerous a magic?"

"I think so too."

The researcher sighed.

"However, the warp gate has already become an indispensable item for humanity."

The warp gate was convenient.

Thus, even if people knew the dangers of the warp gate, it wouldn't disappear, and this was the reality of the continent at the time.

------

After collecting books related to soul absorption magic, Turner, Charlotte, and I returned to the Imperial capital.

We told the commander that we found nothing in the labyrinth. We only mentioned that we returned safely.

No one saw what we found since we had secured the magic books in the saddlebags tied to our horses beforehand.

We decided to keep the underground labyrinth of the Demon King's Castle a secret.

Uncertainty had turned into conviction.

Charlotte was indeed possessed by the soul of the Demon King.

Her current state was no different from that of an Archdemon.

The Demon King had separated his soul using soul absorption magic and fused it with Charlotte's soul.

Whether there was a way to separate them, Charlotte would entrust the analysis of the soul absorption magic to trustworthy royal magicians and find a solution.

"You did well, Reinhardt. Thank you."

"...I didn't do anything in particular."

I hadn't directly helped Charlotte. It seemed that Turner and Charlotte were eager to return to the palace as soon as possible to analyze what they had acquired this time.

There was no reason for me to stick around any longer, and there was nothing I could do.

Before catching someone's attention, I parted ways with the two of them and set out on my own path.

I gained more from this return to the Demon King's Castle than Charlotte did.

There was a bunker in the underground of the Demon King's Castle.

Therefore, Valier wouldn't have died.

And through the numerous magic books there, I would be able to summon Cantus Magna.

I had gained a lot, but my concerns had also grown.

What exactly had the Valier of the past done? Cantus Magna and Valier could both be unrelated, one of them could be involved, or both could be connected.

Had Valier tried to make contact with Cantus Magna like I'm doing now?

Let's assume so.

Valier had used his vast magic knowledge as bait to make contact with Cantus Magna.

Then, Cantus Magna finally completed Akasha through that magic, and it caused some incident. That would be the gate incident.

It's too much of a leap.

But I couldn't be sure that it wasn't the case?

However, I couldn't be certain that it wasn't the case.

And there was one thing that I regretted deep inside.

Soul Absorption Magic.

There was certainly a story about the fusion of souls within it.

What happened to Charlotte could be related to that as well.

Lucinil said she wanted souls.

Wouldn't it be possible that the answer to bestowing a soul upon a soulless being lies within the Soul Absorption Magic?

Although Charlotte was the first one who came to mind, after calming down, I realized that Soul Absorption Magic might be a necessary spell for Lucinil as well.

But now, all the magic related to Soul Absorption has left my hands.

If I finish researching it and find a way to restore Charlotte's original state, will I be able to retrieve the magic books on Soul Absorption?

What excuse should I use if I do get them back?

I didn't think it was a hasty decision, but since Lucinil is helping me, I'd like to help her in some way as well.

The underground labyrinth of the Demon King's Castle.

The bunker.

I would have to share this information with Lucinil and her collaborators and make a decision about Cantus Magna as well.

Amidst these thoughts, I returned to the temple.

"Oh, you're back."

As I returned to the Royal Class dormitory, Ellen was staring at me in the lobby.

You're back.

"You're the one who's back."

Ellen looked at me with a puzzled expression.

"Where have you been?"

"Uh..."

Another secret?

Ellen asked, but her expression showed she didn't really expect an answer, a somewhat resigned look.

She knew better than to expect anything from me, so even asking took courage, but her expression showed she'd accepted that such courage was useless.

At this point, shouldn't I be able to tell her?

Although it might be rude to Charlotte, Ellen already knew that I was helping Charlotte in some way because of the emperor.

I looked around and, after making sure no one else was close enough to hear, whispered softly to Ellen.

"Well, it's hard to explain in detail, but it's because of Charlotte's problem."

"…Ah. Yeah."

Ellen seemed quite surprised that I actually gave her an answer.

"It wasn't dangerous."

"Okay. I got it."

Ellen looked up at me, her voice slightly choked with emotion.

"Thanks for... for telling me..."

"…"

What's the big deal?

Even though I hadn't fully explained the situation, Ellen seemed touched that I shared even a little bit with her, and her eyes welled up with tears. Seeing her like that, an inexplicable emotion welled up inside me.

Trying to shake off the strange feeling, I looked at Ellen with an intense gaze.

"By the way, how was your trip home?"

"Oh, right."

Ellen gasped as if she had just remembered something, then grabbed my arm.

"I have something to show you."

"Huh? W-wait a moment."

"Hurry up."

Ellen suddenly began dragging me somewhere.

------

A short while later.

I was drawn into Ellen's room and found myself blankly staring at the cloak draped over her body.

"What is this?"

"Lapelt."

Ah.

Um.

That thing.

Isn't it that?

"The cloak of the Sun God."

"Oh, right, that."

My brain froze.

"Why do you have that?"

"I brought it from home."

Um.

That thing.

I don't think that's the kind of explanation one should give.

"Why was it at your home?"

"I don't know."

I'm getting dizzy.

"Mom gave it to me, saying I might have to fight the Demon King."

This is too dizzying!