The fusion did not succeed. At least, not in the way Tsubaki had envisioned.
She had underestimated that evil demon.
And she had made a fatal mistake. She thought the demon blood of Muzan Kibutsuji could help her suppress the demon sealed beneath the Tahōtō.
She thought this plan should be feasible.
During the month she had studied that demon blood, she had also discovered that the terrifying regenerative ability it brought was something she could utilize.
As long as she could maintain her sense of self while possessing it.
She could even still use her spiritual power.
With spiritual power added to this power, she should have a certain degree of confidence in suppressing the demon under the Tahōtō.
But reality proved her wrong.
With the demon blood surging inside her, maintaining her state was nearly impossible.
At least, she couldn't do it.
And the 'human-demon' power from Muzan Kibutsuji, not demonic, but something else, was nothing but a lamb to the slaughter before the demon under the Tahōtō.
That was a demon.
A powerful evil spirit sealed for centuries, nearly a millennium.
And so, at that moment,
The moment Tsubaki tried to seal the demon's consciousness, she was immediately backlashed.
Boom!
A dull sound exploded from within that entangled mass of light and darkness.
Tsubaki's body flew backward, crashing into a pile of rubble.
She coughed up blood.
Dark red not the bright red of living blood, but the dark color stained by demon blood.
"Heh… hehe…" Tsubaki struggled to push herself up. Her eyes, now dark red, were full of unwillingness.
But her attention was quickly seized by something else.
In the ruins before her, black mist churned.
The evil demon, not devoured by her
It had instead taken some of the demon blood's power from her body, and together with its own released original power, was re-condensing its form.
The black mist contracted, pressing down.
A silhouette began to emerge.
Very tall.
Nearly nine feet.
Humanoid, but not human.
Its skin was crimson red, like molten lava.
Its limbs were long, with six fingers on each hand, each finger twice the length of a human's, the claws at their tips gleaming black.
Its head was bald. On the bare skull, two deep-set eye sockets glowed with dark red light.
Its mouth split from ear to ear, its teeth interlaced. No lips, only everted dark muscles.
It wore no clothes.
On its red body, a massive hole was visible in its chest, the wound left from being sealed centuries ago, still unhealed.
Inside the hole, dark red flesh walls writhed slowly, as if something was gestating within.
This was the evil demon sealed under the Tahōtō.
A demon, an evil spirit that had devoured thousands of people in a town centuries ago.
The Red Evil Demon.
Shinji watched this scene. Beneath his demon mask, his expression was unsurprised.
He almost felt like laughing.
Devouring the demon under the Tahōtō.
In the stories he had read before crossing over, Tsubaki had indeed done something similar and succeeded. But at that time, she had possessed the Shikon Jewel.
The power of the Shikon Jewel was the true key to suppressing all evil spirits' consciousness.
Without the Shikon Jewel, relying only on a shrine maiden's spiritual power and a few mouthfuls of demon blood to devour a centuries-old demon?
A pipe dream.
The 'human-demon' created by Muzan Kibutsuji was not as strong, nor as useful, as she had imagined!
Using the blood of Muzan's 'human-demon' to fuse with a 'yōkai', it was like using a cup of water to extinguish a mountain fire, and the water smelled of gasoline.
Not only did it fail to suppress, it only fed the other.
So at this moment, Shinji was not surprised at all.
At this time,
He was genuinely unshaken.
While delighted at Tsubaki's misfortune, he also found it troublesome.
Because the two powers had now merged within this evil demon.
The demonic aura of a yōkai, plus the immortal regeneration of a human-demon.
It had become a misshapen monster.
Both a demon and not entirely a demon.
It stood in the center of the ruins, its grey-white body especially terrifying under the moonlight. The hollow in its chest seemed to writhe with new flesh.
Its two deep-set eye sockets slowly turned, surveying everyone present.
Then it moved.
Not to attack.
To inhale.
It opened its mouth, split to its ears, and took a deep breath.
The lingering scent of demon blood in the air, all of it was drawn into its body.
For it, this was pure nourishment!
Its body began to swell.
Under its red skin, muscles grew wildly.
Its height of nine feet rose to a full fathom in mere breaths. The writhing of the hollow in its chest accelerated.
On the dark red flesh walls, new tissue began to grow.
It was absorbing the demon blood, absorbing all power related to 'demons.'
Turning it into its own.
"This is…" Kōyō's voice trembled.
She had read her master's notes describing this demon.
Though, after centuries of sealing, its condition seemed far from its prime, it was still terrifying.
Very terrifying and powerful.
"We can't let it keep absorbing," Kikyō's voice was cold as frost.
She had already drawn her bow.
Three arrows held between her fingers, spiritual power condensed at the tips, not the seal-plus-purification she had used against the low-tier demons, but pure, maximum-output purifying arrows.
Against a yōkai of this level, ordinary techniques wouldn't work.
Absolute destructive power was needed.
Shatter it before it swelled further.
Then, before the fragments could reorganize, shatter them again, until its power was exhausted.
The string sounded.
Three arrows flew together.
White light tore through the night, aiming straight for the demon's head, its chest hollow, and its knee joint, three positions, three vital points that needed to be hit simultaneously to cripple its mobility to the maximum extent.
They hit.
White light exploded.
The grey-white body was pierced by all three arrows. Its head shattered, its chest hollow blown into a larger hole, its left knee blown clean off.
The demon's upper body toppled backward, pieces of flesh flying.
But
It didn't fall.
At the broken knee, new bone and muscle regrew in the blink of an eye.
The shattered head recompleted before the pieces hit the ground, that split-to-its-ears mouth reopening.
The residual spiritual power in its chest hollow was swallowed by the dark red flesh walls. Before purification could even complete, it was assimilated.
The purification effect of the spiritual power only worked halfway.
The demonic aura part was purified. That demonic power, originating from the turbid energy of heaven and earth, was indeed weakened, suppressed, and dispersed by the purifying arrow's spiritual power.
But the regeneration did not stop.
That distorted life force from Muzan's blood was completely unaffected by spiritual power. In the blank areas left after the demonic aura was purified, it frantically filled in, growing back the destroyed tissue.
The spiritual power destroyed its demonic aura.
The human-demon's regeneration restored its body.
Then the demonic aura re-condensed, covering the regenerated flesh.
An infinite cycle.
"I see." Kikyō's brow furrowed slightly.
She understood.
The spiritual power wasn't completely ineffective, it was indeed consuming the demon's demonic aura layer. Each arrow weakened its demonic component.
But that regenerative force restored the body, and as long as the body was intact, the demonic aura would re-condense.
To truly kill it, ordinary methods were now impossible.
Whether spiritual purification or anything else.
Because the human-demon and yōkai components complemented each other, forming a cycle.
But now was not the time to think.
Because the demon was already moving.
Its tall, red body took a step, the ground cracking beneath its foot.
Six-fingered claws swept sideways.
Its speed wasn't great, far slower than Kidōmaru's.
But its power was astonishing. The oppressive force, even approaching that of Kidōmaru, that forest-demon who had perfected speed.
The shockwave from that single claw swipe sent all the surrounding rubble flying, like an invisible wall pressing down.
Yet, in that instant,
Shinji was already in front.
Without any need for words, a silent cooperation: Muramasa drawn, bone spurs bursting from his left arm through his armor, crossing in a block.
Clang!
Metal on metal. Bone and claw collided.
Shinji's body slid back three steps, his feet carving two trenches in the earth.
"Heavy," he said.
This demon's raw strength was on par with Kidōmaru's. Though its speed was far inferior, each strike felt like being hit by a small mountain.
But....
[Lightning-Muscle Sharp Body] activated.
Purple electric arcs exploded from Shinji's entire body, traveling along the bone spurs into the grey-white claw.
Zzzap—!
Lightning scorched the demon's arm.
The red evil demon's skin was burned by the arcs, muscle fibers torn.
Effective.
Lightning was physical destruction, not spiritual power.
Though regeneration continued, it was noticeably slower, the continuous burning of the lightning interfered with the regeneration process.
"Kikyō!"
String sounded.
Destruction.
The fourth arrow.
This arrow wasn't aimed at the demon's body.
But at the ground.
The spiritual power exploded the moment the arrow landed, forming a barrier five yards in radius, a pale blue net rising from the ground, tangling around the demon's legs.
The spiritual power couldn't kill it, but it could hold it.
Even for just a few seconds.
Shinji seized those seconds.
[Bone Soul Transformation] fully activated.
White bone spurs erupted from the earth beneath their feet, piercing through the demon's calves, thighs, and abdomen, pinning it in place.
The spurs were continuously forced out and broken by its regenerative power, but new spurs immediately emerged from deeper to replace them.
Kikyō's barrier binding combined with Shinji's bone spurs.
One locking its movement externally, the other piercing its body internally.
Two entirely different methods, perfectly coordinated in the same moment.
The demon let out a furious roar.
It struggled, tore, its split-to-its-ears mouth spewing turbid black mist.
But it was held in place.
Temporarily.
"Physical damage works on it." Shinji analyzed quickly in the gap between attacks. "Spiritual power can only weaken its demonic aura layer, but it can't suppress the regeneration."
"We need another way," Kikyō's voice came from behind.
She had nocked another arrow but didn't fire immediately.
Her dark eyes simply watched the demon.
"Its regeneration isn't demonic," Kikyō said. "It comes from the blood of that so-called Demon Progenitor you mentioned."
Shinji gripped Muramasa tightly.
He was well-read in the original story; he knew the curse of Muzan Kibutsuji.
And the only weakness of that curse,
He looked up at the eastern sky.
Darkness.
Thick clouds obscured everything.
But at the edge of those clouds, a faint, almost invisible pale grey.
The light before dawn.
In less than an hour,
The sun would rise.