The world line is a world that is infinitely "similar" to modern Japan.

The streets, culture, science and technology, and the lives of the people living there are almost no different from the modern Japan we know.

People go to school, head to work, trains run through the city, and when night falls, buildings and streetlights are lit.

At first glance, it is a world that is no different from the modern Japan we know.

However, there is one major difference.

The people who exist in this world are not humans like us—they are a race called the "Star People."

The Star People are a race that has lived in this world since ancient times, and everyone spends their daily lives as a matter of course.

However, in this world, there exists another world that most Star People do not know about.

That is—

"Front" and "Back."

In the "Front" live the Star People, who lead lives similar to ours.

In contrast, in the "Back" live a race different from the Star People—the "Moon People."

The "Back" exists very close to the "Front," yet it is another world that ordinary Star People cannot easily set foot in.

There are cultures and customs different from those of the Star People, and there are also special powers that only the Moon People can handle.

Approximately a thousand years ago.

The Star People and the Moon People once recognized each other's existence and were very friendly races.

Despite having different cultures and powers, they interacted with each other, shared knowledge, and at times coexisted while joining hands.

However, a certain event caused that relationship to change significantly.

What was the trigger?

Why did the two races begin to fight?

Records detailing the truth have been lost over the long years, and now almost no one knows the exact details.

Eventually, small disagreements turned into large rifts, and the Star People and Moon People gradually became wary of each other.

Suspicion toward each other turned into distrust, and distrust eventually turned into hatred.

And that hatred finally developed into a major conflict involving both parties.

During that battle, the Star People formed a certain organization to counter the Moon People.

Its name is—

"Tensei"

A special organization on the Star People's side whose purpose is to monitor the Moon People, probe their movements, and fight if necessary.

Meanwhile, the Moon People also created their own organization to counter the Star People.

Its name is—

"Tsukuyomi"

A special organization on the Moon People's side whose purpose is to protect the "Back," the world of the Moon People, and counter the threat of the Star People.

Thus, "Tensei" and "Tsukuyomi."

The two organizations have continued to clash for many years to protect their respective races and worlds.

And both the Star People and the Moon People possess special powers.

The Moon People handle abilities using the "Moon" floating in the night sky as a medium.

They draw out powers related to the moon, such as its phases and moonlight, and manifest them as different abilities.

In contrast, the Star People handle abilities using the "Stars" as a medium.

They draw power from the countless stars shining in the night sky and use it as their own ability.

Stars and Moon.

Two races that have different powers yet possess somewhat similar qualities.

The feud that began a thousand years ago has not ended even as the eras have changed.

Right next to the Star People living casually in the modern "Front," there exists the world of the "Back" that no one knows.

And on the other side of that boundary, the Moon People still live quietly today.

This is a story of a thousand-year-old long-standing feud between the Star People and the Moon People, and between "Tensei" and "Tsukuyomi," set in a world very similar to modern Japan.

〈Tensei〉 ・An organization aimed at monitoring and fighting the Moon People. ・Number of members: 4–6

〈Tsukuyomi〉 ・An organization aimed at resisting the Star People. ・Number of members: 3–5

〈Tsukuyomi Ranks〉 Highest Rank

Full Moon

Upper Crescent

Waxing Moon

Lower Crescent

Waning Moon

General Member

New Moon

〈Tensei Ranks〉 Highest Rank

Fixed Star

Upper Star

Morning Star

Lower Star

Nebula

General Member

Starfield