As a reward for aiding the Darato Principality, Jin received an island off the coast of Tobo, a town in the southwestern part of the Principality.
It had never been given an official name and was simply referred to as "Offshore Island."
Jin took ownership of it on a semi-permanent basis—or rather, as his de facto territory.
To the outside world, however, it would be treated as a leased territory.
Jin had leased this land to protect Onogoro Island, which lay about one hundred kilometers to the south-southeast.
For the time being, given their technological level, national strength, and current circumstances, neither the Darato Principality nor the Mimaka Principality had any intention of venturing out to sea.
Yet there was no telling what might happen in fifty or a hundred years.
Of course, an illusion barrier had already been set up on Onogoro Island, making it impossible to spot with the naked eye even if a ship approached.
Furthermore, because the ocean currents surrounding the island were treacherous, no vessel without a powerful propulsion system would dare approach carelessly.
Incidentally, the true nature of these currents had been discovered only recently.
Since Jin and his companions traveled using Warp Gates, they rarely had the occasion to examine maritime conditions in detail.
Shortly before this, Jin and Laojun had been discussing on Hourai Island where the leased territory should be situated.
"So, you're saying that 'Offshore Island' is our best option, Laojun?"
"Yes, My Lord. It is part of our strategy to keep Onogoro Island concealed for as long as possible."
"I don't quite follow. Could you explain the reasoning?"
"Certainly, My Lord."
According to Laojun, the plan was as follows:
They would install a Warp Gate or a teleportation magic circle on that island to serve as a hub teleportation port.
This would make travel by sea inefficient and reduce maritime traffic.
Consequently, the risk of Onogoro Island ever being discovered would plummet.
"We must also prepare defenses against outside threats."
"Let us also construct lodging facilities, tourist attractions, shops, and a hospital."
Without generating foreign revenue from tourists, they would be unable to provide a plausible explanation for developing the island in the first place.
"Let us frame it as an initiative to cater to tourists from the Conference Countries."
Laojun added that they could operate sightseeing vessels primarily along the coastline, steering them well clear of Onogoro Island.
"I see. You really thought of everything."
And so, Jin began the development of Offshore Island.
"Hmm... Calling it 'Offshore Island' forever feels a bit dull."
The first order of business was to give the island a proper name.
"If I remember right, rebun means 'offshore island' in the Ainu language..."
With that in mind, Jin decided to christen it "Rebun Island."
Incidentally, he pronounced it Rebun-jima, not Rebun-tou.
"Well, now that the name is settled..."
Regardless of what kind of development they pursued, they first needed a comprehensive grasp of the island's geography.
Laojun had already generated a detailed map, but to survey the landscape with his own eyes, Jin set out on a reconnaissance flight aboard the Taube Kai piloted by Hope, accompanied by Reiko.
Rebun Island was roughly elliptical, its long axis stretching from the northeast to the southwest.
Its topography was straightforward, featuring a mountain rising near the center. It reached an elevation of 333 meters—the exact same height as Tokyo Tower.
As for the vegetation, the southeastern coast facing the open sea was blanketed in evergreen shrubs, while the northwestern shore along the Inner Sea supported a sparse woodland of evergreen trees five to ten meters tall.
There were birds, but not a single mammal, not even small ones. Insect life was equally scarce, limited to tropical butterflies, a scattering of bees, hoverflies, and small beetles. There were no reptiles or amphibians to be found.
"Did the Origin Clan dislike having small animals around, I wonder?"
"That is quite likely. Considering this was an alien world to the Origin Clan, the native biota would hardly have been familiar to them," Laojun replied over the manacam.
"I suppose that makes sense..." Jin nodded in understanding.
"Now then, what should our next step be...?"
Jin consulted with Laojun once more.
"I'm a bit torn on how to handle the island's natural environment."
The dilemma was whether to preserve the existing landscape for resort development or to artificially alter the vegetation to some extent.
"I believe you may proceed however you see fit. There are clear signs of extensive terraforming by the Origin Clan, meaning the environment has already diverged from its pristine state."
"I figured as much..."
"Indeed, My Lord. The Origin Clan made substantial alterations, particularly in this region."
"Probably because they intended to turn it into a granary belt."
"That was likely their primary objective."
"I see..."
Jin had another concern on his mind.
He had previously developed Kunlun Island into a resort, and he wondered whether he should follow that same formula or take a different approach.
On Kunlun Island, his goal had been to recreate the modern Japanese resorts he remembered.
"Maybe I'll take a different route this time..."
Since making a profit was not his aim, Jin considered keeping the facilities minimal.
"Oh, or maybe I could make it a private villa retreat..."
Rather than building a sprawling resort hotel, he could construct resort condominiums and grant access only to select guests.
"Well, I can iron out those details as we go."
He thought reserving it exclusively for Avalon might also be a fine idea.
"Next up is the Warp Gate, right?"
That was the core of the project.
"My Lord, I believe a direct Gate connecting to Avalon is essential."
"Agreed....As for the other nations... Hmm, that might get too complicated."
Jin concluded that, for now, establishing a link with Avalon alone would suffice.
"Though I'd eventually like to make travel between them much more casual."
"I expect that will become feasible once the situation with the Jagus Principality is resolved."
"True enough."
Since Jin and his team were operating from the shadows, they had no choice but to leave that effort to the Three Principalities and the World Security Guard.
"And then there's the defense system."
An assault from the sea seemed improbable, but one could never be too cautious.
"Maybe I'll build a secret base underground..." Jin grinned mischievously. No matter his age, a man never truly outgrew his love for secret bases.
"Oh, speaking of underground, what about the island's subterranean resources?"
Thinking of subterranean spaces jogged his memory.
"Yes, My Lord. The island appears to have originated as a coral reef, so the bedrock is predominantly calcareous."
"So we're unlikely to find much beyond limestone....What about fossils?"
If rare fossils were embedded in the rock, Jin wanted to avoid reckless excavation.
"Fossils do not appear to be especially abundant, but we will exercise all due caution whenever we dig underground."
"Yeah, please do."
With that, the development plans for the newly christened Rebun Island steadily moved forward.