My Monster Evolution in One Punch Man

"I'm back, Lord Rover. Sorry to keep you waiting!" Hansen called out as he arrived beside Rover, immediately slipping into character.

Thanks to the vast difference in size and strength between them, Hansen's claws, capable of piercing a Demon-level monster with ease, turned out to be perfectly suited for combing through Rover's tangled and bristly fur. The dense coat was tough enough that even most Dragon-level beings would struggle to damage it. Its thickness and resilience made the task of removing embedded rocks and grime particularly exhausting.

Luckily, Hansen had inherited Rover's monstrous physical capabilities. At the very least, he had plenty of stamina and endurance to handle the job. Rolling up his sleeves, he got to work with both hands, scrubbing and massaging deep into the fur. Gradually, Rover's six burning eyes began to narrow in contentment, clearly enjoying the care. A low, satisfied rumble occasionally escaped from its throat.

"Awooo... grrrrr..."

After a while, Hansen exhaled a misty breath and gave a quick signal to indicate the cleaning was finished. Rover stood and gave its massive body a powerful shake. Water droplets flew outward like a barrage of arrows, striking the stone walls around them and leaving small craters in their wake.

The black-furred beast now looked completely different. Its once dull and matted coat had become glossy and smooth, every strand defined and gleaming. Its overall appearance had transformed, radiating a refreshed vitality and power.

In high spirits after the bath, Rover lowered its gigantic head once more, eyes fixed on Hansen with an expectant gleam. It gestured subtly, clearly inviting him to climb aboard so they could head back to the nest.

The second time's always easier.

Without hesitation, Hansen leapt and landed with practiced ease on Rover's broad head. The fur that had been soaked just moments earlier had already dried thanks to Rover's immense body heat. Now warm and soft, it offered Hansen an unexpectedly comfortable ride.

"Awooo! Awooo!" (That was great! Let's do this again sometime!)

With a growl, Rover launched forward. Like a bolt of black lightning, it sprinted up the rock wall in a few powerful strides and vanished down the tunnel.

…

…

Returning alone to his own territory, Hansen was still caught in the afterglow of the experience. The closeness and trust Rover had shown during the ride stayed with him, lingering in his thoughts. It felt oddly like playing a nurturing simulator game, except the creature he was raising could level a city without effort.

If there had been a visible affection meter, Hansen was certain Rover's favorability had already passed the threshold.

Winning over a Dragon-level executive by accident was still a victory.

Yet despite his rapid growth in power, Hansen remained clear-headed. The world around him was still incredibly dangerous. Even within the Monster Association alone, there were at least five individuals capable of killing him instantly.

He was getting stronger, but not strong enough.

Thinking about how to grow even stronger, Hansen made his way back to the underground cavern that served as his personal territory. As he approached, a chorus of chaotic roars, crashes, and shrill screams echoed through the tunnels, growing louder with every step.

By the time he reached the entrance, the scene unfolding inside was exactly what he had expected.

Several Wolf-level monsters were locked in a savage brawl, fighting viciously over the mutilated remains of another creature. Severed limbs and scattered organs flew through the air like grotesque confetti. The stench of blood was thick and overwhelming, fueling the madness until it bordered on hysteria.

The longer the brawl dragged on, the more it attracted others. Nearby monsters, unable to restrain themselves, lunged into the fray, adding to the already spiraling chaos.

Off to the side, a few Tiger-level monsters stood by in silent observation. They watched the carnage unfold with cold, calculating eyes.

Occasionally, one of them would step in under the pretense of "mediating" the fight, only to seize the most gravely injured monsters and carve them open for a fresh meal. It was a brutal and twisted ecosystem where the strong fed on the weak, and the weak fought to avoid being next.

This was the reality of life on the bottom rung of the Monster Association: chaotic, merciless, and utterly lawless.

Hansen remained unaffected. Things had been like this even under Slime Octopus's leadership, and his own rule wasn't going to bring much change. He had no intention of disrupting the natural order that had already taken root here. After all, this chaos wasn't accidental. It was part of a calculated scheme devised by Psykos, the real mastermind behind the Monster Association.

Few knew the truth. Hidden deep within the organization, Psykos was conducting massive experiments based on her theory of "Near-Death Evolution."

That's right. It was basically the same cheat code the Saiyans had in Dragon Ball.

By pushing lower-level monsters to the brink of death, she hoped to trigger sudden, explosive evolution. Her goal was to create stronger monsters, ones that could truly be of use to the Association's higher ambitions.

But in reality, not every monster had a hidden Super Saiyan inside. Most lacked that kind of potential. Those who died in these experiments mostly stayed dead, and their bodies were discarded without ceremony.

Still, Dragon-level monsters were rare, while Wolf-level creatures were plentiful. Even if only one or two Demon or Dragon-level beings emerged from hundreds of deaths, the experiment was considered a rousing success.

The instant Hansen's three-meter-tall, imposing figure stepped into the chamber, the chaos screeched to a halt.

Whether they were fighting, feeding, or merely watching, every monster instinctively froze. All eyes turned toward him, wide with fear and awe. The new Demon-level ruler had returned.

A few of the Tiger-level monsters exchanged glances. They noticed something subtle but unmistakable: his presence had changed. His aura was deeper, heavier, and more unfathomable than before.

Hansen ignored their stares. Even Fang, who rushed over with a sycophantic grin and a string of compliments, was dismissed with a lazy wave of the hand. Without a word, Hansen strode past him and walked straight toward his private chamber.

The trip had brought him more than just experience. It had gifted him with something rare and valuable. He needed to analyze it properly.

Once back inside, he activated his system panel.

SSR: "Swift Wind"

SR: "Monsterization"

"Let's test the SSR first."

With a silent command, Hansen activated the Lv1 "Swift Wind."

Buzz!

A pulse of invisible force erupted from his body in all directions.

The lair stirred as violent winds surged through the chamber, whirling around Hansen with an intensity that matched his rising excitement. His heavy black spiked armor, which normally pressed down on his frame like a burden, now felt incredibly light, almost like a second skin. Every joint, every muscle, was charged with a newfound agility and fluidity he had never felt before. He could sense the movement of air with razor-sharp clarity, as if the wind itself was speaking to him.

In the blink of an eye, his figure blurred. A ghostly afterimage lingered for a split second where he had stood, but Hansen's real body had already crossed the lair and now stood at its far end. The movement had been so fast it resembled teleportation.

"Man, that's fast!" he whispered, wide-eyed.

Even though he had caught a brief taste of this sensation before, Hansen couldn't help but be impressed. His baseline speed now rivaled the burst velocity he used to force out only through combat mode. What once took deliberate effort and brute strength now came naturally.

"This feeling..."

He lifted one clawed hand, the jagged black spikes gleaming under the flickering cavern light. Slowly, he spread his fingers. Wisps of greenish-blue air curled around them like sentient threads, responding to his will, twisting and swirling in a delicate dance.

"Wind energy, huh?"

He could tell that the explosive speed came not from physical exertion but from the miniature cyclones spiraling around and even within his body. They weren't just riding the air; they were part of him. Curious, Hansen began experimenting, attempting to guide and shape the energy more precisely.

Shiiing!

A razor-thin blade of condensed wind, nearly invisible and silent, burst from his fingertips. It shot across the lair with deadly precision, slicing through a protruding rock ten meters away. The stone split cleanly in two, revealing a mirror-like surface at the point of the cut.

Hansen narrowed his eyes. That Wind guy probably used the same mechanism to reinforce his slashes and attacks. The logic was sound, the blade hadn't relied on force but velocity and precision, amplified by the concentrated wind energy.

But beyond simple attacks, there were far more possibilities. That guy was still struggling just to handle the raw power he'd gained from monsterification. He hadn't even scratched the surface of what this wind-based ability could truly do.

Hansen, on the other hand, had no such limitations. Even if this Lv1 SSR version of the power wasn't quite as strong as the original, it could still evolve. He could level it up over time. And unlike its previous wielder, he could use it effectively the moment he copied it.

In truth, it felt like he already understood the nature of wind better than the one who was supposed to wield it by right.

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