In a warehouse located in the Eastern District, far from the Western District of Itogami Island, stood a large computer outfitted with a brand-new generator, communicator, and waterproof casing.
From this large computer extended numerous cables, all connected to the neck of a girl with an expressionless face—like strings pulling a lifeless puppet. The sight was chilling.
The girl's name was Rahn, the last surviving member of Tartarus Lapse—a group infamous for destroying Demon Sanctuaries—and arguably its most important operative.
This was because, despite being a small terrorist cell, Tartarus Lapse had succeeded time and again in toppling Demon Sanctuaries thanks to the trump card Rahn wielded.
Members of Tartarus Lapse called it—Rose.
Tartarus Rose—the devastating power behind Tartarus Lapse's destruction of Demon Sanctuaries.
And now…
"It's time to initiate Rose."
Rahn, devoid of emotion, repeated her mission.
Unlike the other members of Tartarus Lapse, Rahn had virtually no combat ability.
However, her brain housed neural circuits sixteen times more intricate than a normal human's.
With these highly advanced neural circuits, Rahn possessed information-processing capabilities akin to a strategic-grade computer—making her an elite hacker.
Naturally, a living brain could not endure the metabolic strain of such complex processing; the nerves would burn out instantly. Therefore, Rahn's body was reanimated through Necromancy. She was, in essence, a corpse—no longer alive.
This was the darkness Rahn bore.
Each member of Tartarus Lapse carried some form of darkness or tragedy.
Carly, a Beast Man of pitiful strength, was neither fully human nor beast. Abused since childhood, ridiculed as worthless, subjected to violence—she was a lonely outcast in both human and Demon societies, even within a Demon Sanctuary. Ultimately abandoned by her parents and left to starve and freeze, she was saved by December, who brought her into Tartarus Lapse and trained her to become a formidable sniper.
Rogi was a militarized artificial lifeform created to wield fire. When the illegal military experiment behind him collapsed, he was nearly discarded and left to die. December saved him too, brought him into Tartarus Lapse, and led him to destroy the very Demon Sanctuary responsible for his tragic fate.
Rahn was no different—she was a magically-engineered Frankenstein, an experimental subject from an illegal project. Had she not joined Tartarus Lapse, she would likely still be in hell.
This was why December, not Senga Takehito, was the true leader of Tartarus Lapse. Senga merely guided and advised—the members followed December.
Thus, Rahn and the others set out to destroy Demon Sanctuaries, viewing them as symbols of the corruption that had tormented their lives.
And this time was no different.
This time, they would destroy Itogami Island—the site intended for reviving the God of Sin, Cain.
Even before the operation began, Rahn had hacked into the Management Cooperative's system, unleashing a powerful military-grade virus that dismantled the infrastructure from within.
Through connectors in her neck and back, Rahn linked her brain directly to the computer network, gaining far greater hacking ability than any normal technician. Infiltrating the Management Cooperative's system was child's play for her.
Now, she would activate what she left behind in that system.
"Fall, cursed island."
Murmuring to herself, Rahn pulled the trigger in her brain.
At that moment, unrest broke out across Itogami Island.
...
"Boom!"
In a street in the Southern District of Itogami Island, a Beast Vassal the size of a brown bear appeared from nowhere. Roaring madly, it smashed a shop to rubble.
"AAAAAAHHHH…!"
Its master, apparently a vampire, screamed in agony, clutching his head and collapsing unconscious.
Yet even in unconsciousness, the vampire's Beast Vassal remained—rampaging wildly, tearing up roads, buildings, and cars.
"AAAAAAAAAAHHHHHHHH—!"
Terrified citizens screamed, panicking and scattering in every direction.
Similar scenes unfolded all across Itogami Island.
All over the island, Demons suddenly howled in pain and collapsed. Their powers spun out of control, causing widespread destruction and explosions that echoed from every direction in the city.
People ran in terror, but the rampaging Demons gave chase. Various kinds of Demon powers erupted across the city.
Itogami Island had descended into chaos.
Looking closely, the identity registration bracelets worn by the rampaging Demons were glowing ominously red.
On street after street, Beast Men twisted in pain as they underwent forced transformations, vampires lost consciousness mid-mist, and elves erratically summoned Spirits without control. All registered Demons on the island lost control simultaneously.
The Management Cooperative responded immediately, dispatching the Special District Guard in full force to suppress the chaos.
But the rampaging Demons were only a small threat.
The real danger was yet to come.
"Vmmmmm!"
From the bodies of the registered Demons, massive quantities of mana surged upward into the sky.
The mana streams merged, rotated, and fused—forming something that looked like a dense aurora, a swirling vortex, or a beautiful flower.
The flower spun, forming intricate overlapping patterns until it became a massive composite form.
It was a magical circle—so vast that it spanned over ten kilometers, blanketing the sky above Itogami Island.
This was the colossal, rotating, rose-shaped magic circle—Tartarus Rose.
As it spun, it scattered countless petals.
Those petals soon transformed into wild beasts with their own will.
Beast Vassals.
Countless summoned Beast Vassals roared and charged toward the earth below.
Boom! Boom! Boom! Boom!
Across the island, buildings and streets erupted in flames.
Explosions rang out constantly from every direction on Itogami Island.
The island had been assaulted by an army of Beast Vassals—plunged into utter mayhem.