The explosively bursting black water droplets were instantly "evaporated" away. Along with them vanished all the scene within this Innate Domain.
The mountain of corpses and sea of blood, the filthy impurities everything transformed into a drained, desolate gray, as if the next moment it would collapse into dust.
A black sun had risen into the sky, unnoticed until now.
It was a pure black so black that it reminded Hii Kōri of a pigment from his previous life called "Vantablack."
That black sun emitted no light or heat. Rather, it resembled some kind of portal connecting to another dimension, yet its outline was still surrounded by an ominous "halo."
No matter who witnessed it, they would only call it a "black sun."
Hii Kōri slowly exhaled a stream of smoke. The ash from his herbal cigarette fell silently.
Then he watched as the drifting smoke and falling ash slowly flowed into that black sun.
"..."
Accompanied by an almost imperceptible tremor, an eye opened within the black sun.
A single eye emitting a dim glow like molten metal, its surface covered in cracks like overcooled metal, seeping dark red light—part molten lava, part clotting blood.
That single eye's gaze fell downward, locked on Hii Kōri.
Its name: Special Grade Imaginary Overage Cursed Spirit — "Hyakki Kūbō."
In the classification of cursed spirits, there exist two types: "Imaginary Vengeful Spirits," born from combining famous ghost stories and monsters that never actually existed, and "Overage Cursed Spirits," which manifest from conditions such as obsession with a person and the desire to harm them.
The former is represented by the Special Grade cursed spirit Tamamo-no-Mae Incarnate, which Geto Suguru subdued.
The latter is represented by Okkotsu Yūta's "ex-girlfriend," Orimoto Rika.
The Hyakki Kūbō born here was a cursed spirit combining both of these characteristics.
"Kūbō" (Empty Death) is one of the concepts in the sexagenary cycle, roughly synonymous with "Tenchūsatsu" (Midheaven Kill)—referring to the two remaining branches after the combination of the ten celestial stems and twelve terrestrial branches. It is said that during the Tenchūsatsu period based on one's birth stems, misfortune occurs.
On the other hand, Kūbō is also regarded as the "strongest demon" appearing in the Hyakki Yagyō (Night Parade of One Hundred Demons) scrolls.
Of course, the existence of Kūbō, much like "Cain" the progenitor of vampires, is merely a "fallacy" constructed in modern times.
In reality, no demon named Kūbō exists in that scroll. What is depicted is merely a black sphere representing the sun during the "Kūbō" hour the gap between dawn and day.
However, in modern times, a new interpretation emerged: Could that black sun also be a demon? Could the Hyakki Yagyō actually be a hundred demons fleeing from "Kūbō"?
Thus, that black sun also began being depicted as a demon by creators and so the modern demon, Kūbō, the annihilator of all things, was born.
And the curses created within Kirigakure indeed, within the entire abnormal customs of the Land of Water had an extremely complex composition.
Rage, greed, jealousy, hypocrisy, disloyalty, arrogance, rebellion, misanthropy, immorality, cruelty, self-righteousness, madness, laziness, cold-bloodedness, selfishness, stubbornness, deceit, arrogance, obstinacy, foolishness, suspicion, unrest, bloodlust, apathy, baseness, numbness, emptiness... Yet the most abundant among them were hostility and hatred toward others, and "fear" of this world.
Centuries of isolation, oppression, and a history of mutual harm had given birth to the deepest curse—one obsessed with "erasing all things in the world."
This curse had exploited the gap in the heart of the Land of Water's current strongest—the Third Mizukage—taking root within him, gradually draining his remnants, eroding his will, driving him to further the Bloody Mist policy, thereby accelerating its own birth.
And Hii Kōri's understanding, from another angle, shaped the concrete form of this "curse of erasing all things."
Thus was born the most evil most evil cursed spirit: Hyakki Kūbō.
"..."
An unrecognizable sound came from the air.
Not human language, not the cry of any known creature—it was a string of twist "gibberish," as if countless voices had been forcibly shredded and pieced together.
Simply hearing it made Hii Kōri feel an instinctive nausea.
Yet he could understand its meaning.
"Thank... you... for your... help..."
Hyakki Kūbō was "thanking" him.
Thanking Hii Kōri for gathering the curses, for shaping its form, for helping it be born.
Then, the eye blinked.
The next instant, an invisible wave, like a solar prominence, erupts from the black sun.
Even the attack intended only for Hii Kōri could not spare Hyakki Kūbō's own Innate Domain.
The invisible waves stirred up intense traces through space, and the gray-white Innate Domain instantly collapsed, transforming into cracks identical to those on the black sun.
Because he possessed a cursed technique that was similar in certain respects, Hii Kōri instantly understood what it was.
The sight now unfolding was merely the uncovering of the outer remnants of the "Third Mizukage," revealing its true form.
Or rather, a fetus breaking free of the amniotic sac surrounding it.
As a cursed spirit born from hatred and fear of this world, Hyakki Kūbō's inner essence was pure "nothingness."
Its personality was merely a temporary "shell" worn on the outside to prevent its own collapse. Hyakki Kūbō had no so-called inner Innate Domain.
And Hyakki Kūbō's "cursed technique" was simply to further spread its own form of existence.
Not destruction, not annihilation—merely the "return to zero" of all things.
Compared to the effect of Hii Kōri's cursed technique derived from Palm Hatching—Ucchuṣma's Hundred Transformations Sealed Method, which could strip the properties of things and transform them into "blank"—this "zero-returning" power was even more pure.
Even if Hii Kōri used his cursed technique to erase all properties of an object, a meaningless lump would remain. Hyakki Kūbō wouldn't even leave "meaninglessness" behind.
It was like the difference between setting a number to zero versus smashing the calculator, or removing paint versus burning the canvas.
"Ha. So this is what they call 'outside and inside are the same'..."
Hii Kōri let out a genuine sigh. "From that perspective, I'm actually envious of you."
Before the words had faded, he made a move Hyakki Kūbō hadn't expected.
He stepped forward into that invisible zero-returning wave, raised his arms, spread his five fingers, and then fiercely swung his palms forward.
"But—"
Cursed energy poured into his circuit. The cursed technique was woven into form.
"—for me, you're actually the easiest opponent to deal with~"
Palm Hatching. The ability to transform all things into their initial state.
Not "reducing" phenomena from effect to cause, but transforming phenomena from effect into cause, then into the unknown. Turning everything into the original, then into the alien. One could say it was a technique that captured the essence of the term "exhausting possibilities."
And the derived Ucchuṣma's Hundred Transformations Sealed Method was a cursed technique that eliminates the properties of things and gives new properties.
Combating zero-return with possibility, combating erasure with granting—giving meaning to meaningless things, giving order to chaotic things, giving truth to false things.
The Innate Domain, on the verge of being peeled away to reveal ■, was rewoven into something else ambiguous. Before Hii Kōri's cursed technique, Hyakki Kūbō's zero-returning wave could advance no further.
"Ha... I really have to thank you for this. I never thought this technique could be used this way before!"
Driving his cursed technique to "wrestle" with Hyakki Kūbō, Hii Kōri having gained an excellent state from the Six Consecutive Black Flashes unleashed his majestic cursed energy, laughing with unbridled joy.
Of course he'd never thought of using it this way. Before this, he had never encountered another existence capable of doing anything similar.
In fact, facing this cursed spirit Hyakki Kūbō, Hii Kōri even felt a sense of "fate."
If such a thing as "destiny" existed in this world, then their encounter was likely destiny itself.
The sparks of inspiration are more easily kindled in the passion born of fitting battles.
"Those words couldn't be more true—"
"..."
As if responding to Hii Kōri's shout, Hyakki Kūbō also let out an agitated shriek.
Similarly, even with only an outer shell of imaginary personality, it could still perceive what Hii Kōri had done.
A cursed spirit's potential ability is determined at the moment of birth. The only question is how to reach that limit.
For a cursed womb, going through this stage during the formation process was more conducive to its growth.
Special Grade cursed spirits like Jōgo and Hanami, born from overly vague concepts like fear of "the earth" and "forests," held very simple techniques, merely corresponding to the concepts they were rooted in.
But Hyakki Kūbō was born from "hatred and fear of the world." In fact, it was even more vague than them, yet its form was determined by Hii Kōri's cognition.
Naturally, the abilities it possessed also had a certain degree of correlation.
In a sense, he and Hii Kōri were opposite poles.
Seeing that this tentative attack had failed, Hyakki Kūbō, having expanded considerably in scale, immediately prepared its next move.
The molten-gold single eye within the black sun trembled violently. The cracks all over the eye rapidly spread. At the same time, Hyakki Kūbō's imaginary personality further adjusted itself in contrast with Hii Kōri. The twist gibberish gradually transformed into human language.
"[We are cursed spirits born from humanity's hatred and fear of the world.]"
"[Born from the very beginning to return all things to nothing. Everything in this world must perish and be destroyed—all must be destroyed!]"
The cracked single eye suddenly shattered. Amid Hyakki Kūbō's passionate declaration, a mottled blood-red "pupil" was revealed.
"[Our reflection. Our prototype.]"
"[We, Hyakki Kūbō, shall begin era
sing all things—starting with you!]"
"Try it if you can!"
Like a flower blooming, like an eggshell cracking—in the moment that heralded the birth of something—the mottled pupil walls opened in sequence, transforming into thousands upon thousands of bloody arms, each forming the same hand seal.
Seeing this, realizing what it was about to do, Hii Kōri simultaneously formed hand seals and chanted the incantation.
"Oṃ — amogha vairocana, mahā-mudrā-mala, padma, praveśa, pratihata hūṃ!" / "Oṃ — namo samanta-buddhānāṃ, mahākāraya, svāhā!"
Two similar yet distinct voices rose simultaneously. A hoarse, agitated voice and a calm, agitated voice overlapped, chanting opposing incantations.
"Vajradhātu pervading earth, water, fire, wind, and void, now shall shine forth the light of extinction—" / "Vajradhātu pervading earth, water, fire, wind, and void, now shall shine forth the light of deliverance—"
Wreathed in blue-black cursed energy, Hii Kōri leaped toward Hyakki Kūbō, attempting to interrupt the other's Domain Expansion.
But the warring cursed spirit, regardless of his sudden assault, further expanded its own scale.
"Compassion, pity, joy, equanimity—without self or grasping. Birth, aging, sickness, death—all four gates are closed!" / "Who pierces the threefold city is Maheśvara. Earth, water, fire, wind, pleasure, pain, life—all dharmas are born from the palm!"
"Do! Main! Ex! Pan! Sion!"
The already depleted "Innate Domain" collapsed. The domains of the man and the cursed spirit were about to take form.
"Nirvana Quietude: Blank Mandala!"
"Nirvana Quietude" is both an infinitesimal number infinitely approaching "zero" and the eternal state of tranquility reached after extinguishing troubles and the cycle of birth and death.
And in the hands of Hyakki Kūbō—a cursed spirit seeking the return of all things to zero—the meaning of a Domain Expansion bearing this name could only be one thing: ■.
Domain Expansion is the secret art in which the caster manifests their Innate Domain into reality and imposes their own technique upon it.
That is to say, a domain relying on a barrier must be a closed structure.
Thus, Ryōmen Sukuna's skill of directly projecting his domain without relying on a barrier is called a "divine technique."
However, Hyakki Kūbō's domain was different from all the above cases.
Just as its form of existence as "nothingness" suggested, having no so-called Innate Domain, the domain it expanded was not a projection of a mental landscape into a closed barrier, but rather a physical "inversion" of itself—transforming into an infinitesimal point—absorbing all traces of existence from the outside, then eliminating them.
It was almost a tangible "black hole."
Hyakki Kūbō, with the nature of "nothingness," possessed no mass. But once successfully manifested, within seconds, it would be enough to absorb and eliminate the entire Kirigakure Village.
If it were to fall directly downward, deep into the earth's core, it could even destroy the overall structure of the planet.
"Domain Expansion!"
But before that infinitesimal point could kill everything away, Hii Kōri's domain also fully took form in that instant.
"Void Mandala: Cyclic Reincarnation - Ultimate Progressive Nirvana!"