Two hundred and thirty-five years ago, a mysterious plague ravaged the Former Leonard Kingdom. Feared by all, it was named the "magical consumption fever."
The epidemic began in the north and gradually moved south.
The mortality rate was high, and there was no known way to prevent it. Bodies were cremated until reduced to ash, and the kingdom's population was slashed in half.
To escape this nightmare, a plan for exodus was devised.
The destination was the Moon. An ancient magic circle of unknown origin had been preserved within the Leonard Kingdom.
One by one, they vanished into the circle—the king, the royal family, the nobles, and finally the commoners. It was said that not a single soul ever returned.
Jin had heard this story once before, during a research trip to the Former Leonard Kingdom last summer, from a messenger left behind in a basement.
"I have heard of the Leonard Kingdom's past while on the surface," Jin D said. "I wish to speak directly with the Manager of the Base."
There was no immediate answer.
A long silence followed. Eventually, a voice echoed through the area—one that clearly did not belong to Golem No. 28.
《Who are you? You possess the body of an automata, yet your spirit is undeniably human. I have never encountered such an existence.》
The tone was different, but it was the same voice Jin D had heard upon his arrival. This was likely the Manager of the Base.
"I am Jin Nidou. I am a Magi Craft Meister from the surface. The one speaking to you now is a Doppel I created."
《A 'Magi Craft Meister'...? I presume that means you are a leading expert in magi-engineering. And a 'Doppel'...? That is also a name I have never heard.》
"Am I correct in assuming you are the Manager of the Base?"
《Indeed. I was once the Control Brain of the 'Heavenly Ship.' When the 'Heavenly Ship' fulfilled its purpose, the 'Masters' who migrated to Ars bestowed upon me a new duty: to manage this lunar base.》
An astonishing history was being revealed.
The Manager of the Base had mentioned "the Masters." Did it mean the same people No. 700672 referred to?
"Those Masters... are they the people who came to Ars from the far reaches of space? Am I right?"
《That is correct. You are well-informed. Is that also because you are a 'Magi Craft Meister'?》
"Well, who can say? I suppose it is."
In a way, it was only because he was a Magi Craft Meister that he had been able to investigate the Former Leonard Kingdom and hear the story from the basement messenger, and how he had come to meet the servant known as No. 700672 in the demon territory.
Jin D gave a brief summary of how he had reached this point.
《I see. It appears you are someone worth speaking with.》
The Manager of the Base seemed to acknowledge Jin D—and by extension, Jin—as a conversational partner.
《Then, would you tell me how you arrived here?》
"I came by teleportation. Though not via a magic circle; I used a magi-tool."
《Oh? Intriguing. Does that mean it does not require a receiving unit on this end?》
"Exactly."
《There are no transporters within this facility. That is a logical conclusion.》
"Indeed."
《Could it be that you possess a 'Heavenly Ship'... no, a spaceship?》
"I do. I used it to come to the Moon... to Uni."
《As I thought....You are not one of the 'Masters.' However, you appear to possess technology equivalent to theirs.》
"I'm glad you think so, but are you taking me at my word alone?"
《It is more than just words. A portion of this facility was once the 'Heavenly Ship.' Various measuring instruments remain functional. Using them to scan the vicinity of Uni, I have confirmed the presence of the 'spaceship' you mentioned.》
Inwardly, Jin marveled at the capabilities of the Manager of the Base. It clearly possessed technologies that he had either not yet acquired or had not yet developed.
For a time, Jin D continued his dialogue with the Manager of the Base, gathering information.
The most significant revelation was, without a doubt, the "teleportation magic circle."
A piece of lost magi-technology, the teleportation magic circle took time to operate, but it could teleport objects using only about one-fifth the mana consumption of a Warp Gate.
Jin speculated that this was likely because the circular magic circle amplified the mana. However, the receiving end required a paired magic circle. It wasn't a system that could send things to arbitrary coordinates.
Jin found himself dreaming of improving this teleportation magic circle to allow for more flexible destinations.
Then, the conversation turned to a more personal topic.
"...You said the people who migrated from the Leonard Kingdom were wiped out by the plague. Is that truly the case?"
《It is ninety-nine percent true.》
Before Jin D could ask what that remaining one percent meant, the explanation followed.
《There were survivors.》
It made sense. Magical consumption fever was a disease that became more severe in those with less mana. Out of tens of thousands of people, some must have survived thanks to high personal mana reserves.
Because the fever was a disease unique to Ars, the Manager of the Base's delay in identifying and treating it had contributed to the tragedy.
《There were approximately one thousand two hundred survivors. Since then, roughly nine generations—about two hundred and thirty years—have passed, and those one thousand two hundred have dwindled to two.》
Apparently, every couple had only ever been able to produce a single child. If that were the case, it was inevitable that they would all but vanish after nine generations. Furthermore, there was no guarantee of a balanced birth ratio between males and females.
《Of those two, one passed away recently. The last survivor is now of advanced age.》
"I see..."
Between the disease and the population collapse—no, it was essentially an extinction. They had fled to the Moon to escape the fever, but they could not escape their ultimate fate.
"Still, I'm surprised the people of the Leonard Kingdom thought to flee to the Moon... to Uni."
《In the first place, that country was the one that received the most benefits from this place.》
Yet another new fact. Jin D asked for more details.
《The 'Masters' belonging to this 'Heavenly Ship' were the ones who landed in the Leonard Kingdom.》
It seemed they were a different lineage from the people who had landed in the demon territory. It was a plausible story; there was no reason to assume there was only one Heavenly Ship.
(The Former Leonard Kingdom reportedly had little interaction with its neighbors, so perhaps they walked the path to ruin because their blood became too concentrated... inbreeding.)
Back on Hourai Island, Jin formed a hypothesis. There was no way to verify it, but it allowed him to reach a sense of closure.
"To change the subject, was the strict division of the residential areas a countermeasure against the disease?"
《Correct. The survivors practiced a policy of 'going nowhere and accepting no one,' sealing themselves inside a block with no physical entrances or exits. Teleportation is the only way to move between sections.》
The ultimate shut-ins, Jin thought, though he kept the comment to himself.
"Is that person content to simply accept this destiny?" Jin D asked.
《Yes....Jin-dono, I have just received instructions from that person. They wish to meet you.》
The Manager of the Base's tone shifted suddenly.
The slight pause just before the shift suggested it had been communicating with the survivor. Jin gave his consent immediately.
"If they are willing to meet, then anytime."
At a time like this, using a Doppel was a massive advantage. Even if it were a trap, his true body would be perfectly safe.
"What should Anne do?"
《As she is also an automata, they have said she may accompany you.》
"Then, let's go."
《Proceed straight and enter the room at the end of the hall.》
Jin D and Anne moved as instructed.
While controlling the unit, Jin wondered what had caused the shift in the Manager of the Base's tone, his mind wandering to minor details.
A magic circle was etched into the floor of the room at the end of the hallway.
(This is a room the Shinobi Squad missed...)
Jin wondered if there were other secrets hidden here. He had Jin D and Anne stand in the center of the circle.
《We shall now move.》
The mana trigger was applied to the circle, and a few seconds later, Jin D and Anne had teleported to a different room.
《This is inside a separate facility.》
The environment was notably different, even to Jin D's sensors.
First, the gravity. While it had been nearly 1G in the previous area, here it was roughly 0.8G.
Next, the temperature. It had risen from about 20 degrees Celsius to 27 degrees. The humidity, previously very low, was now around 50 percent.
(It's probably adjusted for the health of the elderly survivor.)
While Jin was making these deductions, a golem appearing nearly identical to Golem No. 28 manifested.
《Please, follow me.》
(A demon or a serpent... we'll see what crawls out.)
Jin held the old dramatic sentiment in his heart.
As told, Jin D and Anne followed the golem deeper into the facility.