36. Black Darkness Hell
"Oni are grudge spirits that have reached a certain realm," her master, Shihei Rin, had once said.
"Some are born as exceptionally powerful yokai due to overwhelming resentment from their past lives that transcends the laws of this world, but most grow after death through devouring souls."
Over long years, they assault and consume yokai like me or humans with spiritual powers, gradually fattening their starving souls. Once they've repeated this feeding enough for their soul's size to surpass a certain threshold, they reach that realm—"that is an Oni."
Ghosts capable of manifesting their grudges into reality. Monsters far beyond ordinary yokai. Not only did they possess superior physical prowess, but they could wield 'incantations' like exorcists. Unique entities on a completely different level from mindless yokai that charged without thought.
So, how many souls must one devour to become such an Oni? In ancient texts left by shamans of old—likely penned by someone who once harbored the same curiosity—it was said that typically, ten thousand souls must be consumed.
In other words, an Oni was a yokai that had evaded exorcists for ages and devoured at least ten thousand of its own kind. Creatures not just strong, but inherently cunning and greedy by nature.
"Yokai are beings of envy and greed. They can bulk up their flesh with the souls they consume."
They couldn't hide their growing power forever, so many were eventually discovered by shamans. Yet facing an Oni was an incredibly arduous task even for them. Combat against one was utterly different from ordinary yokai.
The grand shaman and master, Shihei Rin, gazed at Sawamura Cento before her and murmured gravely,
"An Oni that has devoured countless souls and exorcists isn't simply ten thousand yokai by raw count. Due to the awakening of its soul, it possesses more than double that strength."
Even she, who usually laughed as cheerfully as Ichimaru Shiki, wore a solemn expression at that moment.
"If you ever encounter one, run."
That memory suddenly resurfaced.
'……Can we win this?'
Sawamura Cento wondered.
Kitagawa Kenichi was half-retired, his stamina depleted and a massive wound on his shoulder. Eris pretended to be fine, but she'd already exhausted most of her mana. Only Cento herself, the shaman who had paced herself, had any reserves left.
She coldly calculated their combined strength and gauged the power of the monster approaching leisurely from the front.
A wolf-humanoid Oni.
"Well, well, I underestimated you kids since it was just rookies, but you've got some bite."
The creature approached with a relaxed expression, appraising them one by one.
Its sharp claws gleamed with aura—the telltale light of one who had ignited their energy. Pathetic compared to Ichimaru Shiki's, yet unmistakably aura.
"Guess I'll just have to kill you all here."
A high-level technique proving a swordsman's mastery, a blade that cleaved anything beneath steel. A skill mastered by only the rarest humans—and now wielded by a yokai.
'This is tough.'
The opponent's level was no joke. Even if they could win, it would cost lives. One of them—or all—might die in the clash.
After long deliberation, Sawamura Cento abandoned the fight.
Shiki had wanted them to hold out as long as possible, but risking death here was reckless.
'If your life is ever truly in danger, remember me without fail.'
She recalled Ichimaru Shiki's face from when he'd said that to her before. Sly as ever, but...
'I will come to save you, without fail.'
That line, at least, she believed.
Cento sighed and gripped the brooch pinned to her chest. The gem flashed once as she channeled mana, murmuring,
"Shiki."
Sawamura Cento called Ichimaru Shiki's name without a shred of doubt.
· · · · ·
"......Huh?"
Cento's eyes widened as she clutched the brooch. Her slightly parted lips clamped shut, trembling with rage and bewilderment. Her pupils shook wildly before she squeezed her eyes shut.
'I will come to save you, without fail.'
But nothing happened.
'......Why?'
Was Kenichi right? Had she truly been abandoned? Then why give her the brooch? Hopeful torture? Or had something happened to him? Could he not enter due to the spirit vein's barrier?
Various suspicions swirled in her darkened vision, but no answers came.
Still, what needed doing now was clear.
"───Cento! Intercept it!"
At Kitagawa Kenichi's urgent shout, Sawamura Cento opened her eyes and surveyed the battlefield with a cold gaze—or tried to.
"Now, who should I kill first?"
......The foe was an Oni. Likely a special one among them. Its combat prowess rivaled a human sword saint or grand shaman.
Facing it head-on was folly. She might endure, but Kenichi couldn't.
"Kenichi, fall back."
"What?"
Sawamura Cento first called back Kitagawa Kenichi, who had already drawn his sword and risen. He'd been the frontline all day, so he looked baffled at the order, but she repeated firmly,
"Fall back. I have a plan."
"......Got it."
At her insistence, Kenichi grimaced but retreated behind her.
"Hmm?"
Eris was gathering her energy from the rear, preparing spells for the Oni's charge. Thus, Cento ended up at the forefront.
The wolf Oni tilted its head curiously at the situation.
"What's this, shaman? Eager to be my first meal?"
A question unworthy of reply. Cento glared at the yokai with murderous eyes, crouching and pressing her hand to the ground. It looked like she was bowing to it, making the Oni's lips twitch wider.
"Begging for mercy, perhaps..."
──The price is the souls of the vanquished.
The voice suddenly echoed from the heavens. All life in the space felt the mana shift. The wolf's mocking expression froze instantly.
It was obvious who was invoking this.
Sasasak—the ink-written characters crawled from beneath the hem of the hand on the ground, spreading across the earth to form positions.
The wolf lunged late to stop it, but the characters completed a single incantation.
──Shadows, the hellish rite.
Sawamura Cento unleashed crimson eyes reflecting the full moon's light and initiated the chant.
"O Cruel King of the Five Paths Wheel, manifest here the Black Darkness Hell."
⟨ Black Darkness Hell ⟩
In that instant, the world inverted.
The ground's shadows fell, the night sky crashed down. All darkness enveloped the world, and with a kuwagagagagang!—the spirit vein's realm filled with pitch black.
· · · · ·
Black Darkness Hell.
A pitch-black space where nothing was visible.
'Can't see a damn thing.'
In the world of total darkness, the wolf Oni, Kaikoku, tilted his head.
The incantation's scale was too vast for a mere girl. Overwhelmed, he'd feared some catastrophe—but
'I can feel the ground underfoot and the scent of soil.'
Only sight was stolen; other senses remained intact. In a world blind but otherwise normal, his superior sense of smell should give him the edge. Shamans had fools among them, but she hadn't seemed that stupid...
'Why pull this stunt?'
He soon learned the answer.
Kuwaaaaaang!—A sudden nearby explosion caught his left shoulder.
Kaikoku grimaced in pain but sought the shaman or mage's position. To cast a spell, mana flow should be detectable, yet
'As expected.'
Nothing. Not even the blood-scent trail from the boy earlier.
They'd deliberately erased their traces. With sight gone, pursuit was near impossible.
"Hmm."
Kuwaang! Even as another blast tore his left abdomen, Kaikoku stroked his chin, devising a counter.
"Simple enough."
The wolf Oni closed his eyes. Sight was useless anyway, so he focused on one sense.
Taste and touch were irrelevant now, smell too guarded against.
──Thump-thump.
A heartbeat echoed.
· · · · ·
......Meanwhile, outside the spirit vein's barrier.
Hmm.
In a world dyed ashen gray, the narrow-eyed man stroked his chin and muttered,
"What to do about this."
He'd come to rescue them, but couldn't enter.