On a dark night beneath a full moon.
In the Imperial University library, Yeriel was secretly studying magic.
Lately, staying in Hadekain had begun to feel strangely burdensome, so she had come down to the capital for a while.
The cause was, of course, the Altar’s attack on the Imperial Palace.
These days, every single day was nerve-racking for Yeriel.
Of course, there was no one who would dare demand a bloodline verification from a Yukline, but that was only “so far.”
“……Whew. I’ll do the rest later.”
Around ten at night, she wrapped things up roughly and came out onto the university grounds, trudging along. Naturally, there were many escort knights hidden in the shadows nearby.
Given the state of affairs, it was only to be expected.
“Hm?”
Yeriel, who had been about to return to Deculein’s mansion, suddenly spotted a group of mages.
The members of the “Common Magic Research Club,” including Epherene, Maho, and Drent.
—But how are we supposed to ensure safety with this? Does everyone have any ideas?
—Well…… Ephy, can’t we just use something sturdy?
—Then it won’t fly. It’ll be too heavy.
—What if we enchant it with weight reduction?
—That’ll make it too expensive.
They were gathered around some broken object, chattering among themselves.
Curious, Yeriel approached them.
“What are you all doing?”
“Hm? Ah~ Lady Yeriel.”
Epherene smiled brightly and waved. Yeriel narrowed her eyes.
“How many times do I have to tell you, it’s not lady, it’s senior…… No, more importantly, what are you doing?”
“It’s a power machine. We’re preparing something to submit to the fair.”
“Ah…… That thing? It’s a power machine?”
A power machine smashed to pieces. It was too round to be called an airplane, had no wings, and had some sort of propeller attached to the top of it.
“We’re thinking of naming it something like ‘Helicoptercio Sauron Mister Sparta.’”
“Really? That’s way too long. But why are you struggling with it by yourselves? Ask Deculein to help you. He’s your supervising professor in name, isn’t he?”
Even as she said that, Yeriel secretly clenched the hem of her clothes.
She could not approach Deculein too closely.
She could not act friendly, nor could she act kind.
In public, their relationship was extremely bad, and it had to remain bad.
Because she was Deculein’s most fatal “Achilles’ heel.”
“That will probably be difficult. The professor seems busy these days.”
It was Drent who said that. Epherene beside him chimed in as well.
“Yes. I showed this to him too, but he totally shot it down. So we’re modifying it now, but……”
Anyway, it’s hard. I don’t think he’ll help us.
Epherene sighed and looked at the stock certificate in her hand. Before long, a sly smile spread across her face again.
“Hehehe…… I’m rich.”
Leaving the muttering Epherene behind, Yeriel summoned a little courage. She looked up at the towering Magic Tower.
The seventy-seventh floor. Deculein’s office was still brightly lit.
Yeriel said,
“Then should I try talking to him?”
The members of the Common Magic Research Club opened their eyes wide. Epherene asked back,
“Really?”
“Yeah. I mean, even if we’re on bad terms, I can talk to him more comfortably than you can. I happen to have something to say to him too.”
“Oh! Thank you!”
Yeriel gave a faint smile and turned around.
She went straight into the Magic Tower and got into the elevator.
“Whew……”
Ding—!
And so, the moment she reached the seventy-seventh floor with a deep breath.
—……If you mean Yeriel.
Deculein’s voice seeped out from the office. In the dark corridor, a taut current of mana hung in the air.
Yeriel immediately concealed herself and looked toward that place.
Through the half-open door of the Head Professor’s office, some light was flickering. And there was not one presence, but two.
Deculein was with someone else……
—That child is not even up for negotiation.
* * *
……Thirty minutes earlier.
In the Head Professor’s office, I had to some extent “understood” Dikailen’s art magic.
First, my overall one-line evaluation was as follows.
“It can be called a theory of the century.”
Dikailen’s magic, based on engineering and science, biomedicine, and magical theory, literally made it possible to create “living, moving works of magical art,” and its compatibility with other branches of magic was also excellent.
If most magical theories were “pure mathematics,” such as geometry or analysis, this magic was closer to practical art.
“However……”
First, the greatest obstacle was that it used “demonic energy” as a medium.
If mana could produce output similar to this, then it might become the light, salt, and ultimate goal for many mages who had chosen the alchemy branch.
“It is not impossible.”
Right now, I was searching for a clue to that method.
“But, alchemy, is it.”
Even among mages, “branch discrimination” certainly existed, and among them, alchemy was a fairly looked-down-upon branch.
Historically, before Dikailen, mages who majored in alchemy were called “technicians,” and only after Dikailen was its value acknowledged.
Even now, among mages of Ether rank, Roserio was the only one in the alchemy branch.
There must be some reason that Dikailen’s personality became so extremely twisted.
“A curriculum will be necessary.”
With the main quest close at hand, monopolizing knowledge was no longer necessary.
I would discover as much talent as possible and raise them in a short time. If the continent were to perish because of greed, what could be more disgraceful?
And so……
Whoooooosh——
At that moment, wind rushed in from beyond the window. However, I had never opened the window, and the intruder knew that fact as well.
I glared at that spot and twisted my lips.
“……The Red Demon of the desert, is it.”
An unexpected uninvited guest, and the second leader of the desert.
The woman with quite a bounty on her head—“Elesol”—spoke in sign language.
—That’s right.
“Why have you come. Do you not value your life? Or is Ellie nearby?”
—You do not need to know that. I will ask without preamble. Why did you not keep the promise of Rohalak?
“Promise? Are you talking about Rohalak’s gas chamber?”
—Yes.
Elesol distorted her face. She signed roughly and released mana.
—If you do not keep the promise, we will have no choice but to tell the Emperor the truth about “her.”
“……”
For an instant, my expression hardened. Without a word, I straightened my posture.
I lifted my chin and glared down at that insolent Red Demon as if to skewer her.
“……If you mean Yeriel.”
—Yes.
“That child is not even up for negotiation.”
—What—
I seized Elesol’s hand as she tried to move it with 「Psychokinesis」. She stiffened like a stone statue.
“I will say it again. If you have one and only hope, it will be that child. Do not even think of doing anything foolish.”
“Hup!”
The mana she released with a sharp shout disrupted my 「Psychokinesis」.
As expected, she was a Red Demon of some caliber.
“For a deaf-mute, you certainly know how to shout.”
—Do you think the Emperor will stay still after learning that truth? Negotiate properly, Deculein. The reason I came here personally on purpose is because I, too, think as you do. Yeriel is our hope.
She moved her fingers delicately.
She formed each word precisely.
—Mutual. Assured. Destruction.
“……”
—If we tell the Emperor that truth, you will die, and we will die as well. So at least show that you are trying to negotiate with the Emperor. You permitted the construction of the gas chamber far too easily.
I quietly looked at her.
A faint, mocking laugh escaped me.
It was such a ridiculous threat.
—What is so funny?
“Yeriel. That child is my younger sister before she is a Red Demon.”
—……
“If a threat to that child’s safety arises because of the likes of you, then I swear it. In the name of Yukline, I will exterminate your clan.”
The darkness of night colored the office.
Elesol showed no reaction. She simply sighed with an impassive face.
—Even if the Emperor finds out, will you not abandon her?
The answer to that insignificant question was obvious.
It was not even worth pondering.
“Even if the end is ruin.”
—……
Elesol closed her eyes for a moment.
She remained like that, as though thinking, then nodded with a hint of laughter.
—Very well. You are trustworthy. So we will tell you as well. We have obtained the Altar’s next plan. It is Yuren.
“Yuren?”
—We need your help.
I frowned slightly.
“Was delivering information your objective from the beginning?”
—Yes. We are not foolish enough to threaten you with our lives on the line. Whether ally or enemy, probing what lies in one’s heart is important.
“Hmph. You are not brainless, then. In that case, what is their objective?”
—As you know, not far beneath Yuren is the volcano of the “Ashes.” A dormant volcano. One that has not stirred for three hundred years.
With that one sentence, I roughly understood the Altar’s objective.
“The volcano, is it.”
—That is right. They intend to make the volcano erupt artificially. If that happens, not only the Ashes but Yuren as well will be in danger. The entire mountain will collapse.
Later, in the expedition to the Desolate Land and at the final stage of the main quest, Yuren would be an indispensable hub.
So much so that if Yuren perished early, clearing the game itself would become impossible.
“How fortunate. The magic I am learning these days happens to be of the alchemy branch.”
—It is not a volcano that can be stopped with mere alchemy magic.
“Hmph. There are many mysteries in this world that cannot be understood by the limited insight of people like you.”
—……
Elesol frowned, but soon shook her head and signed.
—I ask for your help. This time, we will support you from the desert as well. However, before that…… may I ask just one thing?
I nodded.
—……
The eyes of the woman who had fallen silent for a moment looked at me.
Then, with somewhat trembling signs, she asked a certain question.
—What is the difference between the Red Demons and Yeriel? You hate the Red Demons, yet cherish Yeriel. Is such contradictory coexistence possible?
I answered immediately.
It was not even worth thinking about.
“It is simple. Yeriel is a Red Demon, but the Red Demons are not Yeriel. Or are you Yeriel right now?”
A cold wind brushed past again. Elesol’s hair swayed forlornly.
Soon, she smiled and nodded cleanly.
—I understand. Professor Deculein.
At the same time as those signs, she leaped out the window and concealed herself.
“……However, do not misunderstand.”
The Red Demons. The most complicated clan in this world.
“Chief of the Red Demons.”
Whether they were listening or not, I did not know.
“I do not hate you. Rather, I merely find you pitiful and pathetic.”
Saying that, I rose from my chair and opened the office door……
“……”
A dark corridor. Yet moonlight seeped in through the window, illuminating certain droplets clinging to the floor.
Moisture that sparkled transparently.
Evidence of someone who had been here until just now.
“Tch.”
Of course, with 「Iron Man」’s five senses, I had faintly felt a presence.
I had left it alone because I thought it was Elesol’s bodyguard.
“……Was it Yeriel?”
I silently gazed at those tears that remained like tracks.
* * *
……Three days later.
Inside the VVIP cabin of the airship heading to Yuren.
I was glaring at the formula written on magic paper. At the same time, I was thinking about the contents of the letter I would send to Yeriel.
It was the simultaneous use of the left and right brain.
“Tch.”
For reference, both were difficult.
What was I supposed to say to my younger sister, who had shed tears that day, and this damned “conversion formula”—
How was I supposed to solve it?
“Professor. What’s that?”
Suddenly, Epherene in the seat beside me showed interest. She had been sneaking sidelong glances at it, waiting for an opportunity, since earlier.
“It is a conversion formula.”
“Ahem…… It looks really easy, though?”
“……Easy?”
How should I deal with this insolent fellow? Should I flick her on the forehead, or strike her with words?
“Then is this supposed to be hard?”
Well, this problem did look easy at first glance.
It was only one or two lines, and if one thought of it as a math problem, its appearance was extremely simple.
[Conversion: A/(B+C) - B/(A+C) + C/(A+B) = 1]
To describe it roughly, there were only three independent equations of about this level.
“What is it a formula to convert? What are A, B, and C?”
“It is a relational formula between demonic energy and mana that I am trying to find. Demonic energy and mana are mutually similar, powers that ultimately share the same ‘origin,’ so such a simple conversion formula came out.”
“Hmm~ Give it here. I think I can solve this.”
Epherene snatched the paper away with a whoosh.
“Let’s see……”
I glanced at her and shook my head.
……Fifteen minutes later.
“It’s unexpectedly hard to solve, isn’t it? But it still looks easy.”
To this foolish girl, I showed half of the solution to the problem.
“Take it. It’s the solution.”
“Huh? Ah, I think I can solve it too…… Um. What is this? What does this even say?”
The moment she accepted the solution, her eyes widened.
I twisted the corner of my mouth and said,
“They say two heads are better than one. Go on, look it over and think about it.”
“…….”
The problem itself was only a single line, but its solution filled hundreds of pages.
No, since it was still incomplete, even hundreds of pages would not be enough.
“It is a conversion formula that mobilizes not only magic formulas, but every mathematical concept including functions and geometry, and even posits ‘Void Mana,’ a kind of ‘mana-neutral state.’”
Epherene gulped.
Had she truly thought converting demonic energy into mana would be so easy?
“Sometimes, what appears simple on the surface is the most difficult.”
“Aha…… But are there theories even you can’t solve, Professor?”
At her words, I shrugged.
“The verification takes far too long. It might be easier if I roughly construct the conversion formula and then determine its validity through the method of elimination, but a single confirmation takes three months.”
“What’s the experimental method?”
Her sudden barrage of questions was irritating, but curiosity was an essential virtue for a mage.
“You inject mana based on this ‘conversion formula’ into a mana stone containing demonic energy, then wait three months for the result. Now close your mouth.”
I focused my eyes on the solution again.
The airship was still flying toward Yuren.
But then.
Tap, tap—
Epherene touched my shoulder again. I glared at her.
“Epherene. Do you perhaps want to go skydiving? Right now.”
“Huh? No. More importantly, this.”
She took out her pocket watch.
“There’s another way to use this watch. Look.”
She placed a piece of some snack on top of the watch, then infused it with her mana.
In an instant, the hour hand and second hand of the pocket watch began to move rapidly.
Ticktickticktickticktick──
During that time, Epherene kept her eyes closed, and a smile slowly rose to my lips.
After about thirty seconds had passed.
“……Phew! How is it?”
Epherene proudly lifted the snack. I examined it closely.
In a mere thirty seconds, it had grown so moldy it was inedible, then soon crumbled like dust.
It was the result of “time travel.”
“How far into the future?”
“Exactly three months. This much is nothing.”
Epherene crossed her arms and lifted her nose proudly.
To this girl, who looked cute to me for almost the first time, I said,
“……You’ve finally done something useful for once.”
“Hehehe!”
At that moment, the papers containing the conversion formula and solution suddenly fluttered down beneath the seat.
Immediately afterward, the magic paper itself vanished without a trace.
Naturally, it was the effect of some spell.
“Ah! What the heck!”
Epherene was the first to react.
“No!”
I myself was perfectly calm, yet she sprang up from her seat and shouted as if screaming.
“Damn it, thief! Over here! There’s a thief! I said there’s a thief———!”
The VVIP cabin had a capacity of only thirty people. At the sudden shriek, all of them frowned and looked back and forth between Epherene and me, but whether it was a thief or not, it did not matter.
“Guest, please calm down. There cannot possibly be a thief in this VVIP cabin.”
“What do you mean, there can’t! They just took it with magic! Ah, I never learned 「Reverse Tracking」 because it’s Harmony-type. What do I do? Professor, can you do it?”
“……Epherene. Shut your mouth.”
Because there was nothing special about the conversion formula itself.
Even if one knew that solution and formula, they could not solve it in the first place—
“No, I’m telling you Professor Deculein’s magic theory has been stolen! A theory that hasn’t even been announced yet—someone seems to have just snatched it away!”
“Pardon? Is that true?!”
At that, the flight attendant turned to me with an expression of tremendous shock.
“…….”
Without saying a word, I imagined tomorrow morning’s Imperial headline.
[Exclusive! Deculein’s New Magic Theory Stolen.]
“It’s worth nearly 100 million elne—no, what am I saying, 100 million elne! It must be worth 1 billion elne!”
“That can’t be!”
[Exclusive!!! Deculein’s New Magic Theory Worth 1 Billion Elne Stolen!]
And then, an alarm blared throughout the airship.