After absorbing and gaining control of the Special Grade Cursed Spirit, Suguru obtained information about it.
This was a Special Grade Cursed Spirit born long ago during the chaotic era of the Western Middle Ages, born from humanity's fear of demons.
Due to the chaotic spread of information at the time, depictions of demons varied greatly, but certain traits remained consistent. They were tall beings with gaping jaws capable of devouring a person whole. They granted people's wishes and claimed their souls as payment after death.
Later, a witch sealed this Special Grade Cursed Spirit. By a twist of fate, it was brought back as an offering by a fleet from the Eastern Great Country and eventually ended up in an island nation.
"A Special Grade Cursed Spirit, huh?" Suguru murmured softly.
After understanding the situation surrounding the Cursed Spirit, he turned toward Eichi and looked down at the two Cursed Spirit sisters subtly encircled.
"Aren't you going to tell us about yourselves?" he asked.
Eichi immediately understood what Suguru meant.
"Leave the next fight to him. You should rest."
When Eichi had fought the Special Grade Cursed Spirit earlier, Suguru had already sensed the immense fluctuations of Cursed Energy.
However, the situation before him made Suguru cautious.
It was his first time seeing a Cursed Spirit with intelligence, and the energy radiating from it was not to be underestimated.
Originally, he planned to quickly eliminate this strange Cursed Spirit before assisting Eichi, but the Spirit's actions made him even more confused.
She had actually offered to help deal with the Cursed Spirit fighting Eichi.
"Who are you, and why do you want to help us?"
Uncertain of her intentions, Suguru began probing the Cursed Spirit in front of him.
After some communication, he detected no malice.
Still, fearing that unpredictable complications might occur if she entered Eichi's battlefield, Suguru decided to absorb her first before heading over.
It was then that she displayed an ability that made him wary.
She wrote something in a pink notebook, and Suguru felt most of the Cursed Spirits he had summoned being forcibly unsummoned, returning to his Technique space.
Only Cursed Spirits of Grade 2 and above were immune to the unsummoning.
Her physical combat ability was weak, but her raw strength was surprisingly great, preventing him from subduing her immediately.
"Your companion's situation is a bit dire," she said calmly.
Realizing he couldn't finish the fight quickly, Suguru finally accepted her suggestion.
Although she was troublesome, she wasn't an insurmountable threat. Right now, supporting Eichi against a Special Grade Cursed Spirit was the priority.
If anything went wrong, he could decide whether to fight or retreat together with Eichi. Hesitating would only put them at a disadvantage.
And so, the events unfolded as they did.
"My story? That starts fifty years ago," the girl Cursed Spirit said, a hint of nostalgia in her voice.
"But I doubt you'd want to hear such a long story."
She suddenly stuck out her tongue playfully.
The barrier enveloping the entire school began to fade. The girl stepped forward and embraced the Crimson Being.
Under Eichi and Suguru's astonished gazes, the crimson color covering the Crimson Being's body slowly faded, as if she had turned into an ordinary girl.
Bathed in the rising morning sun, their figures turned into particles of light and disappeared.
"We'll leave our story to you. We hope you like it. Goodbye."
Facing the dawn, the girl smiled blissfully, holding her younger sister as they dissolved into the sunlight.
The lingering barrier emitted faint ripples, and an illusion appeared in everyone's minds.
The Onoyama Family's ancestors had once included a Jujutsu Sorcerer, which had temporarily elevated them to nobility.
However, after that Sorcerer's death, no other Sorcerers were born in the family, and their brief glory quickly faded.
Fortunately, the ancestor had left behind considerable wealth, allowing the Onoyama Family to live comfortably.
Then everything changed fifty years ago.
The younger sister was lured away and murdered by a neighbor while returning from school.
That night, guided by clues and neighbors' testimonies, the police and father found the neighbor's house.
What the father discovered inside was his daughter's dismembered body, chopped into pieces with an axe.
Upon hearing the news, the mother suffered a mental collapse, staring at her daughter's corpse in madness.
The father and older sister were also consumed by grief.
Later, the mother recalled an old family record stating that their ancestor had once possessed a jar containing a sealed demon brought from the Eastern Great Country.
Legend said that the demon would grant wishes but claim the wish-maker's soul as payment.
With only a shallow understanding of Jujutsu and Cursed Spirits, she clung to her last hope. She tore open the seal, intending to sacrifice herself to revive her daughter.
Feeling the air grow cold, she brought her daughter's corpse and made her wish to the unseen demon.
The mother died peacefully within an illusion created by the Cursed Spirit, while the father, who arrived too late to stop her, also met his death.
The Cursed Spirit then turned its gaze toward the younger sister's corpse, whose soul had not yet dispersed.
It intended to devour the soul as well.
The Onoyama sisters possessed latent talent as Jujutsu Sorcerers, but because their family lacked a proper legacy, that potential had never been discovered.
The older sister, arriving just moments after her father, witnessed her entire family lying dead. The immense shock caused her to awaken her Technique, the "Incredible Game."
This Technique allowed her to deploy a barrier where she could establish "game rules," and anyone inside the barrier could not violate them.
However, the rules would only take effect after a short time and could not directly cause harm to others.
The newly awakened barrier was no larger than a single room.
The disturbance caught the Cursed Spirit's attention, and it turned toward the older sister.
Like a predator sensing new prey, it began to move closer.
Paralyzed by fear and drained from using her Technique, the older sister could only watch as the Cursed Spirit approached.
Fortunately, its slow movements gave the barrier time to activate.
Driven only by the thought of saving her sister, the older sister's Technique automatically generated rules aligned with her wish. Her Cursed Energy was continuously siphoned and transferred into her younger sister's body.
The younger sister's body began to recover, and her soul, stimulated by the Cursed Spirit, gradually awakened.
Perhaps due to the mysterious bond between twins, under her sister's awakening and the influx of energy, the younger sister also awakened her own Technique—one that allowed her to create and recall Clones.
When a Clone was recalled, anything enveloped by its Cursed Energy would return with it.
After awakening, the younger sister summoned a Clone and used it to push her older sister away before she could be devoured. The Clone was swallowed in her place.
Another Clone hid the weakened older sister behind a pile of debris.
The Cursed Spirit swallowed the Clone infused with the older sister's energy, and as her energy depleted, the older sister slowly died.
The Cursed Spirit sensed something strange, but since the older sister's presence had vanished and it had indeed consumed something with her energy, it dismissed the thought and turned its attention to the younger sister's soul.
Satisfied with its new prey, it enslaved the powerful soul that had awakened a Technique.
The Cursed Spirit then released the younger sister's soul, cursing it into the Cursed Spirit known as the Crimson Being.
After commanding the Crimson Being to hunt for it, the Cursed Spirit turned into black mist, merged into her body, and fell into slumber.
If a Jujutsu Sorcerer's body is not properly handled after death, it can easily generate Cursed Spirits.
Thus, a Sorcerer's corpse must be dealt with through Jujutsu.
The older sister died from overexertion of Cursed Energy and life force, but her Technique's effect persisted, amplified by her obsession with her younger sister.
As expected, she transformed into a Cursed Spirit.
"Younger sister, younger sister," the older sister murmured endlessly.
"What is a younger sister? What is a younger sister?"
In confusion, her barrier automatically generated rules to stabilize her mind, gradually restoring her sanity.
Over the following decade, the Crimson Being killed and enslaved nearly a hundred souls for the Cursed Spirit, while the older sister relentlessly pursued her, trying to free her younger sister.
Eventually, she realized the Cursed Spirit was mostly asleep and only required negative emotions, not lives.
Using her Technique's barrier, she began influencing her sister's actions.
After many attempts, a "game" of finding a body emerged.
Since her younger sister's body had been mutilated before death, this obsession formed the foundation of the game. It easily drew the Crimson Being's attention.
Schools, filled with emotional students, provided ample negative energy to keep the Cursed Spirit dormant.
The older sister refined the game's rules, ensuring that anyone killed within the barrier would not truly die, and that those who completed it would forget the events, dismissing them as a nightmare.
In the thirty years since, almost no one had actually been killed by the Crimson Being.
Through this, the older sister successfully confined her younger sister to the school, maintaining the Cursed Spirit's slumber while seeking a way to save her, until the arrival of Eichi and Suguru.
(To be continued.)