"Hm?"
Hearing Kurosawa Ren's voice, the Sludge Monster finally realized there was still another person present. It turned its head and stared directly into Ren's eyes, curiosity flickering briefly across its murky face.
"This is your Quirk?" the Sludge Monster sneered dismissively, completely disregarding him. "Pink eyes?"
Seeing this, the corner of Ren's mouth lifted slightly.
Daring to look directly into the Sharingan—only an idiot ignorant of its true nature would do something so reckless.
"I'm waiting, kid," the Sludge Monster said mockingly, the disdain in its eyes growing thicker. "Let me see what kind of ability you've got."
"Why are you still standing there?" Bakugo Katsuki snapped angrily. "Why aren't you hiding?!"
The Sludge Monster's refusal to listen only added fuel to Bakugo's already short temper.
Ren ignored Bakugo entirely. His gaze never left the Sludge Monster.
"You want to see my ability?" Ren said calmly. "That's exactly what you'll get."
"—Whoosh."
In the very next second, the world before the Sludge Monster shattered.
The raging flames vanished. The streets disappeared.
What remained was only silence—and emptiness.
"Where did he go?" The Sludge Monster finally felt a flicker of panic, though it tried to suppress it as it twisted its body and scanned the surroundings.
"I once heard about an experiment conducted overseas," Ren's voice echoed from all directions, ghostlike and impossible to trace.
"Stop playing tricks, brat! Get out here!" the Sludge Monster roared, writhing and lashing out wildly—but there was nothing.
"If someone were locked in a dark, silent space," Ren's voice whispered directly into its mind, "how long do you think they'd last?"
The Sludge Monster's panic deepened. Regret crept into its thoughts.
It had been reckless. It should have investigated Ren's Quirk first. Provoking him so carelessly was a mistake.
"Hmph. I don't believe this can last," it muttered to itself, desperately trying to stay calm. "This is just temporary. Everything will return to normal soon."
"To be honest," Ren said softly, unseen, "I'm curious too. Let's test it together."
In the darkness, the three tomoe within Ren's eyes spun violently.
In an instant, the world was plunged into absolute darkness—a dead silence so complete that even the concept of life vanished.
…
-----Forty Hours-----
At first, the Sludge Monster remained relatively calm.
With no one to speak to, it began muttering to itself, babbling nonsense Ren couldn't understand.
After eight hours, its behavior started to change. It laughed at times, cried at others—its mind slowly unraveling.
By thirty hours, it could no longer endure the isolation. It staggered aimlessly, slamming into invisible walls.
This place was an illusion.
No matter how violently it crashed, no marks would remain.
But the pain did.
By forty hours, hallucinations set in. The Sludge Monster collapsed into despair, teetering on the edge of total mental collapse.
It screamed endlessly. When it couldn't find a wall, it slammed its head against the ground.
"Tsk, tsk… only forty hours?" Ren's figure slowly emerged from the darkness. "I had prepared another gift for you."
Seeing Ren was like seeing salvation.
The Sludge Monster rushed forward and clutched Ren's leg desperately.
"Please! Let me out! I was wrong—really wrong! Please!"
Its mind shattered, dignity long gone. It wanted only one thing now—escape.
Ren crouched down, smiling gently.
"A gift shouldn't go to waste," he said. "Whether you like it or not, you're receiving it."
"Wha—?!"
The Sludge Monster's pupils shrank violently.
In the next instant, it found itself bound to a cross, completely immobilized, unable to use its Quirk.
The darkness and silence peeled away.
The world turned scarlet.
A blood-red moon hung in the sky.
At some point, Ren appeared before it, holding a delicate, crimson dagger.
"This was supposed to last three days," Ren said calmly, turning the blade between his fingers. "But judging by your condition… one day will do."
Normally, sharp weapons were useless against a Sludge-type body.
But this was Ren's world.
And here, he decided everything.
"—Pshhk!"
"AAAHHH!!!"
The dagger pierced cleanly into the Sludge Monster's body. No blood flowed—but the pain was absolute, driving its eyes bloodshot.
…
-----Back to Reality-----
The Sludge Monster endured nearly three days within the illusion.
In reality, only a single moment passed.
As consciousness returned to the real world, relief flooded through it. The Sludge Monster collapsed instantly and lost consciousness.
At that moment, the world had never felt so beautiful.
"Huh?" Bakugo Katsuki stared in disbelief as the monster that had been fighting him moments ago suddenly dropped to the ground.
Remembering the strange exchange between Ren and the Sludge Monster, Bakugo turned sharply toward him.
"What did you do?"
There were only two people present who could have fought the Sludge Monster.
And Bakugo was certain it was Ren.
Ren's eyes had already returned to normal. He glanced at Bakugo briefly, then turned away and walked off without stopping.
"Nothing," he said casually. "I just let him get a good night's sleep."