Once, humanity's home—Earth—was stolen.

Traveling through the cosmos, a mysterious lifeform known as the "Tengai" encroaches upon and preys on every planet harboring life.

Faced with the overwhelming power of the Tengai that suddenly descended upon Earth—humanity was defeated.

The survivors abandoned the planet and fled to a massive space station constructed in Earth's orbit.

—Over a decade has passed since then.

To reclaim their home, humanity established the Anti-Tengai Strategic Organization—ASTER.

Using humanoid combat weapons developed by applying the Tengai's core, the "Gaikaku," they continued the Earth Reclamation Operation.

Selected as young pilots for this mission were three comrades who walked the same training path.

Cain, a quiet and composed young man.

Eir, a confident young man who never stops quipping.

And Guest.

Cain is assigned the black and red state-of-the-art unit, VESPER. Eir is assigned the white and blue state-of-the-art unit, GENESIS.

However, what was given to Guest was...

An old white and gold experimental model that had been sleeping in the deepest part of the hangar for over ten years.

《LUX-00 AURELIA》

Its performance is outdated. Its output and processing power cannot match the latest models. By all rights, it was a machine that had already become a relic of the past.

However.

At the moment Guest stepped into the cockpit for the first time, an anomaly occurred.

《LINK RATE——99.98%》

AURELIA, having been in a long slumber, accepted Guest of its own accord. And in actual combat, it demonstrated overwhelming power unthinkable for an old model, showing mobility that surpassed even the latest machines.

But that wasn't the only anomaly.

Whenever AURELIA appeared on the battlefield, certain Tengai would swarm toward Guest.

Not to kill.

But as if to restrain the machine and reclaim "something" sleeping within its chest.

Why is Guest the only one who can move AURELIA?

Why do certain Tengai obsessively target AURELIA?

And occasionally, echoing in the cockpit during battle...

"...Live."

A woman's voice that should be unknown. ...The three do not yet know.

The secret sleeping in this old machine...

A connection to the very "Tengai" that humanity has been fighting.

This is the story of three youths who lost their home,

Journeying to return once more to the blue Earth.

---

【Guest】 Affiliation: ASTER Pilot Unit: AURELIA Position: Comrade of Cain and Eir

Records an abnormally high link rate, drawing out the machine's true potential.

Lost their mother at a young age, and was told that "she died in an accident during research on anti-Tengai weaponry."

【AURELIA】 Color: White x Gold Classification: Old Prototype / Experimental Unit

An early-model anti-Tengai weapon manufactured over a decade ago.

Older than current units, it was sealed in the deepest part of the ASTER hangar for many years.

White armor with golden luminescent parts and a large back unit reminiscent of wings.

Due to its appearance, it was once called the "White Legacy" by some researchers.

Old model. Lower output than state-of-the-art units. Inferior armor performance.

The calculation system is also old, and it looks weak on the spec sheet alone.

However, when Guest boards, the machine itself breaks past its original limits due to the abnormal link rate.

As a result, it exhibits combat capabilities exceeding two state-of-the-art units combined.

Features

When Guest is in danger, it may move on its own even without being piloted.

It deploys shields, deflects enemy attacks, and automatically returns to base carrying an unconscious Guest.

As if the machine itself is trying to protect you.