Watching the aura around Sakura Matou surge at a rate visible to the naked eye, Ren Kuroda decisively changed his original strategy.The magic power he had been using to resist "All the World's Evil" shifted—into absorption.
Ren's thinking was simple. He wouldn't absorb that abomination with his body. Instead, he would let the magic power he had released into the surroundings do the absorbing.That way, even if something went wrong, at worst he could simply abandon that portion of his magic.
More importantly, his stock of Lower-Grade Yokai Power Crystals was almost completely exhausted, and Medea and the others still hadn't shown any sign of emerging. If he didn't change tactics now, he wouldn't be able to hold on much longer himself.
Thus, an extremely bizarre phenomenon appeared around Mount Enzō.
Within the pitch-black darkness where one couldn't see their own hand, the sludge-like "All the World's Evil" was being pulled by two massive forces of suction.A small portion flowed toward a violet-haired少女, whose expression had grown unhinged as the aura around her continued to swell.But in terms of sheer volume, the vast majority of the "All the World's Evil" was now being swallowed by Ren Kuroda's magic power.
Even though it was his magic absorbing it, the enormous mass of negative emotions contained within "All the World's Evil" still flooded into Ren's mind the instant contact was made.
Ren did not possess Sakura Matou's "corruption-compatible" nature. Turning "All the World's Evil" into usable power was far more difficult than he had imagined.
Rage, jealousy, hatred—countless emotions surged into his consciousness all at once. The sensation was eerily similar to the first time he had ever activated Half-Demon Transformation.
An endless tide of negativity began urging him toward brutality, whispering for him to destroy everything within his sight. His eyes instantly turned blood-red, like a beast ready to tear its prey apart.
Already in a half-demon state, the blood of the oni within him had completely overwhelmed his human side. Now, under the influence of "All the World's Evil," his emotions were rapidly slipping toward the most primitive, bloodthirsty instincts of demonkind.
Just as Ren was about to surrender to that instinct and fall back into the oni's most primal state of slaughter—
Thud.
The Nichirin Blade in his hand suddenly seized control of his arm and smacked him squarely on the forehead with its blunt spine.
"Ren, you idiot! Are you trying to become a complete puppet of power—a mindless monster?!Even if you want that, I certainly don't plan on becoming a butcher's tool! I'm counting on you to awaken me fully one day, you know—so pull yourself together already!"
The sudden venomous, mature female voice in his head—paired with the sharp pain in his forehead—instantly snapped Ren out of it. The blood-red haze faded from his eyes, and his mind regained clarity.
Fully conscious again, Ren realized what had just happened and felt a chill run down his spine.
He had actually lost consciousness, even if only briefly—almost exactly like the first time he had used Half-Demon Transformation.
But the difference was terrifying.
If he lost control during Half-Demon Transformation, once his magic ran dry, he would revert to normal.But if he lost himself under the influence of "All the World's Evil"…
If he couldn't wake himself up, he would truly become a corrupted Heroic Spirit.
Waiting for the power of "All the World's Evil" to be exhausted was a fantasy. That thing was born from the accumulated negative emotions of the entire world. As long as humanity continued to produce negativity, its source would be infinite.
And was it possible for the entire world to stop producing negative emotions?
No.Not even remotely.
If it weren't for the fact that he was absorbing it through magic rather than direct physical contact—combined with the resistance he'd gained from Half-Demon Transformation, and the timely intervention of the blade spirit—Ren would have fallen completely.
Realizing that even indirect absorption carried such danger, Ren made up his mind to cut off and abandon that portion of his magic.
However, just as he was about to do so, the magic that had absorbed "All the World's Evil" began to change.
Ren's magic field had previously been labeled by Kiritsugu Emiya as an incomplete Reality Marble.But after absorbing the power of "All the World's Evil," that incomplete Reality Marble began to rapidly perfect itself.
Before, Ren's half-finished Reality Marble did little more than plunge the surroundings into darkness and use overwhelming magic to seal off an area, disrupting external magical interference.
Now, the darkness grew even deeper.
And from the ground, clumps of black sludge began erupting one after another like mushrooms after rain.
Though these masses resembled "All the World's Evil," they were mixed with Ren's magic, granting him a certain degree of control over them.
Previously, aside from darkness and faint whispers of oni gods, there had been no actual creatures within his Reality Marble.
Now, the sludge writhed and twisted—slowly taking on humanoid forms.
After further distortion, they transformed into upright beings with blue skin, tusked mouths, horned foreheads, and samurai armor clad around their bodies.
Others might have found these creatures unfamiliar.
But when Ren saw them, he froze.
These were unmistakably oni—members of the demon race.
And Ren quickly realized that these oni formed from "All the World's Evil" radiated terrifyingly vicious, malevolent auras. Their magical power was anything but trivial.
If converted into yokai power, each of these oni would rank at C+ to B-class at minimum.
As for numbers—
They covered nearly half of Mount Enzō.
There were thousands of them.
Most importantly, among this horde of black-sludge oni were several distinctly special individuals.
They were far larger than the others, wielding massive guandao instead of standard swords. Each rode a jet-black warhorse with a horned forehead, snorting heavily as it stamped the ground.
Unlike the regular oni soldiers, whose presence hovered around C+ to B-class, these towering figures radiated A-rank power.
There were five such oni generals in total.
Then, a system notification rang out.
"Ding! Congratulations, you have acquired a new skill.Skill Name: Reality Marble (Unnamed)Skill Rank: S-rank to SS-minusSkill Description: A supreme thaumaturgy in the Nasuverse world, said to be closest to 'True Magic,' capable of materializing the user's inner world.Due to amplification by the power of 'All the World's Evil,' your Reality Marble has been enhanced. Enemy units within this domain have a chance to suffer fear, blindness, disorientation, and other abnormal states.Negative emotions generated by afflicted enemies—fear, rage, jealousy, and hatred—will become nourishment for the oni soldiers within this Reality Marble, further strengthening them."
The sudden system message left Ren utterly stunned.
Things had escalated far too quickly.
Just moments ago, he had been ready to abandon this half-baked Reality Marble altogether. And now, that same "junk prototype" had suddenly become a skill with a potential ceiling of SS-rank.
This was the first SS-tier skill Ren had ever obtained.
Before this, he had been dragged into the Nasuverse without triggering a quest or earning any reputation points, and he'd honestly thought the trip was a complete loss.During the struggle against "All the World's Evil," he'd even thought he might lose everything he had.
But now?
Not only did he feel no regret—he felt like he'd hit the jackpot.
Fair is fair. Even if he was technically a stowaway in this world, the gains he'd made here rivaled those of any other world he'd visited.
A partially awakened blade spirit alone was incredible—but this Reality Marble was downright absurd.
Thousands of oni soldiers at C+ rank or higher, plus five A-rank oni generals?
This was insane.
This single force rivaled the combined might of the Oni Dōin faction from the Nurarihyon world plus the yokai forces of his home world.
Sure, this oni army could only operate within the bounds of the Reality Marble—but in a large-scale battle, that was more than enough.
And their strength wasn't even capped yet.
As long as enemies within the domain generated negative emotions under the influence of "All the World's Evil," these oni would continue to grow stronger.
That was precisely why the skill was rated S to SS-minus.
At present, it was only operating at S-rank strength—but it had room to grow.
"With oni as the core, and this pitch-black environment…" Ren muttered, grinning."Then let's name this Reality Marble 'Oni Domain.'"
Though the Holy Grail contained an enormous amount of "All the World's Evil," it was still the result of long-term accumulation.
Now, thanks to the combined efforts of Ren Kuroda and Sakura Matou—
That black sludge was visibly shrinking by the second.