Ren felt an immense amount of energy filling his entire body. The limit that had been preventing his growth was swept away by the overwhelming surge of power. He could feel his level of existence rising continuously as his strength climbed with it.
More and more energy overflowed from his body along with his spiritual power, eventually condensing into countless threads that wrapped tightly around him. Finally, they formed a massive cocoon that enveloped both Ren and the entire Hero Association headquarters.
Although it was already late at night and few people remained inside the headquarters, there were always some who stayed in the building overnight. Without even realizing it, they were bound by the threads.
After the enormous white cocoon formed, faint strands continued spreading outward through the city.
Those who were sleeping had no way of noticing the threads wrapping around them. Even the night owls who were still awake failed to perceive the strands that seemed to exist and not exist at the same time.
A shut-in who had been playing games all night shook his head, rolled his neck, and muttered in confusion, "Strange. How can I still feel sleepy at night after sleeping all day? That doesn't make sense. According to my usual schedule, this should be when I'm most energetic. What's going on?"
However, he did not think much of it and assumed he was simply not feeling his best that day. He adjusted his headphones and returned to slaughtering enemies on his computer.
What he failed to notice was that his spiritual energy was being steadily drained through a white thread. Although the amount being extracted was extremely small, it was still being consumed, which explained his growing fatigue.
The white threads did not continue draining spiritual energy for long. They only absorbed enough to spread throughout the entire city. Once everyone had grown drowsy, the process stopped.
As a result, even after dawn arrived, everyone in the city remained trapped in a deep sleep, including the powerful heroes.
It was not until the sun had risen high into the sky and every attempt to contact the city from the outside had failed that the Hero Association branches in other locations realized something was wrong.
By then, it was already too late.
The enormous white cocoon shattered.
Ren stepped out and stretched his body, feeling the far greater power within him and the level of existence that had already risen by an entire rank.
He even felt that if his current self were to fight his former self, he could kill him within ten seconds.
Advancing by a single rank had brought about a complete evolution.
He felt as though he and his former self were no longer even the same species. The difference between them was simply too vast.
"Haha... Hahahaha!"
At first, Ren laughed quietly.
Then his laughter grew increasingly wild and unrestrained.
Even the God lurking behind the scenes was probably no more than a Fourth Rank existence.
And now, Ren had reached the level of the gods described in legends.
As long as he continued growing, even planets would eventually be nothing before him.
That was the kind of power that had once existed only in his fantasies.
Now, he could truly feel it.
Although he had only just reached the Fourth Rank, in the world of One-Punch Man, aside from Saitama, whose strength appeared limitless and continued growing without end, and Boros, the approaching Dominator of the Universe, there was no longer anyone capable of stopping him.
Once his newfound power erased his fear, Ren did not return to his previous carefree and indulgent mindset.
Instead, he decided to eliminate Kou completely.
Once he received the System's reward, even if Saitama came to kill him, Ren would only need to purchase an item capable of banishing him.
Then this world would become his private domain.
Just like the worlds he had visited before, he would make everyone revere him as a king and worship him as a god.
Everything in the world would operate according to his will.
Ren smiled and entered the main control room of the Hero Association headquarters.
Using the equipment inside, he connected to the communication devices of every reachable S-Class Hero.
"Greetings, S-Class Heroes. This is Ren Kanzaki. From this moment onward, you will obey my orders."
"I'm sure many of you believe I have gone insane or that this is some kind of joke, but I assure you, I am completely serious."
"The entire Hero Association headquarters is now under my control. That includes every citizen in this city, along with the wealthy sponsors who provide the Association's funding."
"They are unharmed for now. They are merely sleeping peacefully."
"But believe me, if any of you question me or attempt to cause trouble within this city, I will have no choice but to show you exactly how I can kill those ordinary people right before your eyes."
"You may take some time to confirm what I have said. Once you have done so, carry out my order."
"Find the former S-Class Hero, Kamen Rider Kabuto, who has already transformed into a monster."
"Kill him, or bring him to me."
"You have forty-eight hours."
"If forty-eight hours pass without a satisfactory result, then I will regretfully cause one-quarter of this city's population to die in agony."
Without waiting for the S-Class Heroes to respond, Ren ended the transmission.
He sat in the central chair and hummed a tune, tapping one finger rhythmically against his knee.
The spiritual threads spread throughout the entire city began weaving patterns above it, gradually forming what resembled an enormous formation.
News of the incident spread rapidly.
Media outlets in every city began reporting on what had happened.
No one understood why an S-Class Hero had suddenly turned against the Hero Association.
Without exception, everyone who entered the city to investigate, including B-Class and A-Class Heroes, collapsed unconscious shortly after crossing its borders.
Mechanical units sent into the city were dismantled within moments, reduced to piles of shattered components as though countless invisible threads had sliced through them.
After several attempts to test the situation, the S-Class Heroes and personnel from the Hero Association's other branches finally confirmed that Ren was not bluffing.
Only forty-five hours remained before his deadline.
Tatsumaki, who had the worst temper among the S-Class Heroes, wanted to launch a direct attack and eliminate the lunatic immediately.
However, the other S-Class Heroes persuaded her not to act.
The destructive force of Tatsumaki's battles was simply too great, and Ren was holding the entire city hostage.
If a fight broke out, the resulting destruction and casualties would be impossible to estimate.
In the end, Tatsumaki could only let out an irritated snort before flying away to search for Kamen Rider Kabuto.
At that moment, a man with unkempt hair and a dirt-streaked face stood outside a shop, watching the news.
He wore tattered clothes and an old, dusty cowboy hat that covered most of the upper half of his face.
The man stood there for a long time.
After a period of silence, he quietly adjusted his hat, revealing the face that every hero was currently searching for.
Kou.
(To be continued.)