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The short winter break ended, and from the day after we returned to Canalford Academy, the new term began.

“All right, just as I warned you, we’ll be holding an academic test. It’ll include material from the third term as well.”
“We know, we know! Let’s just get started already. If we don’t, everything we crammed is gonna leak right out of our heads!”

It had been a while since I’d heard an exchange like this between Mr. Tanutanu and Vannabelle. The post–winter break test was a comprehensive academic exam covering both what we’d already learned and what we were about to study again. Anything that fell under the preview material counted as bonus points, and since the total scores were tallied by class, it seemed Vannabelle had studied especially hard.

“All right—begin!”

The test papers were handed out, and the sound of pens scratching across paper echoed through the classroom all at once. I started with the review questions first, then moved on to the problems from the preview range.

The preview section that counted for bonus points was broadly divided into two topics: the Human–Demon War, and this continent itself.

*“Describe the supernatural abilities wielded by the demon race and their characteristics.”*

For someone like me, who had experienced the Human–Demon War in my previous life, this was an extremely easy question. The demon race wielded supernatural abilities known as Gehenna. As phenomena, they closely resembled magic, but abilities beyond what magic had yet achieved—such as gravity manipulation and spatial teleportation—had also been confirmed. It had been made clear by Pure Eye ability users that these powers did not use aether as a medium. Even in the present day, their exact principles remain unexplained, but since sacrifices were used when performing large-scale Gehenna, it was presumed that souls served as some kind of catalyst.

That should be about right. As I filled in my answer sheet, Alfe’s words suddenly came back to me. She had said that the fire magic Ignis Dulan used didn’t rely on aether. Perhaps what the Pure Eye ability users saw when witnessing the activation of Gehenna had been something similar. Still, there was no way a normal human could wield Gehenna, so there had to be some other mechanism at work. At the very least, the demon race I knew had been far more purely evil than this.

Now then, the next question—

*“This continent has no official name. Why is that?”*

Ah right, that was the case. The people of the Holy Kingdom had tried to name it the Holy Flower Continent, after the Three Holy Flower Goddesses they worshipped, while the people of the Arcadia Empire, where we lived, had attempted to name it the Black Dragon Continent for the same reason—after their own god. Wars had broken out between the two nations time and again, but even to this day no decisive victory had been reached. As a result, neither name had ever been established as the official one.

Of course, the people of the Free City Alliance in the southern part of the continent, who had not taken part in the wars between the two nations, as well as the Canado people of the northern grasslands, continued to use the old-calendar-era name, North American Continent¹. However, since the civilization of the Old Humanity was considered taboo within both the Arcadia Empire and the Holy Kingdom, they could not openly use that name. And so, in the end, this continent had no official designation and could only be referred to by the various colloquial names used by each country.

The final question was a very brief one: *“Explain the Demon Realm.”*

Since there had already been questions about the demon race, I had expected as much, but it seemed the Demon Realm itself had not yet been destroyed and still remained. To be more precise, the demons were able to connect from another world to the human realm by some means, and humanity still lacked a way to completely prevent this.

That said, there was no need to go into great depth for this question. Judging by how little space had been provided for the answer, they only wanted to check for a minimum level of knowledge.

In that case, the answer was simple.

The Demon Realm was the stronghold the demon race had established on this continent when they invaded from another world. Its full extent remained unknown, as the entire region was covered by a thin black membrane known as the Veil of Darkness. According to one theory, a gate leading to another world existed there.

Good grief. That had dredged up some unpleasant memories.

Even if the demons’ movements were not particularly active right now, there was no guarantee they wouldn’t once again become a threat like they had during the Human–Demon War. If the worst were to happen, what could I even do then?

²

***

Once the academic test ended, the textbooks for the third term were handed out.

It was a good opportunity, so I figured I should take the time to check my own knowledge against the current state of affairs. When it came to the demon race, extreme caution was unavoidable, so in reality there shouldn’t have been much progress in research—but—

When I looked up the relevant section in the textbook, it was exactly as I’d expected. Alongside explanatory notes were illustration images I remembered seeing back during the Human–Demon War: two moons, a red sky, withered land, purple water, and a black forest.

Because the Demon Realm was covered by the Veil of Darkness, sunlight did not reach it. One passage claimed this was because demons avoided the sun, but it seemed sunlight itself was not actually their weakness.

In place of a sun, two moons floated within the Veil of Darkness: Karna, which governed light, and Idra, which governed darkness.

The celestial laws of the human realm did not apply there. The Veil of Darkness itself functioned as the sky, and as Idra revolved around Karna, a cycle of day and night was produced. When Idra circled Karna three times, the two overlapped and night fell. After circling three more times, they separated again, and day returned.

The light of Karna, red like blood, was said to be intensely hot, scorching the land until it became barren. Inside the Veil of Darkness, the influence of Karna dyed the daytime sky a blood-red hue, while grotesque plants unique to the Demon Realm—unlike anything in the human world—underwent their own evolution, forming vast black forests.

The role of nourishing the withered land was fulfilled by the purple water that flowed out from a hole known as the Gate of the Underworld. This purple water poured endlessly from the gate, forming a sea called the Sea of Corruption.

The reason it was called the Sea of Corruption was that the purple water deeply eroded the land that had originally belonged to the human realm, and because it was a powerful toxin to life forms of this world. Naturally, it was not only undrinkable—mere contact with the skin could cause unknown infectious diseases—so approaching it carelessly was strictly forbidden.

Come to think of it, there had been an alchemist who accompanied the army during the Human–Demon War who succeeded in filtering the water of the Demon Realm. If I remembered correctly, a copy of that paper had also been recorded in Ars Magna, so it might be worth checking later.

According to the latest report, remnants of the demon race that had been defeated in the Human–Demon War were said to be living inside the Demon Realm, but since their forces were small, they had apparently been left unattended for many years. Now that I thought about it, back when I had been Glass Dimelia, there had been rumors in the Holy Kingdom about the existence of an exorcist organization that investigated the interior of the Demon Realm—but whatever became of them? Perhaps the one who had written this report was a descendant of that organization after all.