One Punch Man: Heroics Start with Dual Kamui

Mangekyō Sharingan…?

Shinji blinked in surprise at the system prompt. He already had both Kamui eyes, so why had the system just rewarded him with another Mangekyō Sharingan?

Was he supposed to switch between two pairs now? Alternate between sets like changing outfits?

It didn't make any sense. But before he could overthink it, the system chimed in with an explanation.

[Alert! Host can fuse the dual Kamui Mangekyō Sharingan with Shisui Uchiha's Mangekyō Sharingan to obtain the Eternal Mangekyō Sharingan!]

...Wait, seriously?

Shinji's eyes widened. He was stunned, but more than anything, he was excited.

This was it. The one upgrade he had been dreaming about. The Eternal Mangekyō Sharingan wasn't just a cool power boost, it was an essential evolution. No more blindness, no more recoil from overusing his eyes. Just pure, unrestricted ocular might.

(AN: Someone was complaining that ocular power is a Chinese novel thing, but the term is related to eyes. So, using that word is not wrong for Sharingan.)

So, what are the pros? He'd now gain access to Shisui's legendary techniques, like the infamous Kotoamatsukami, the genjutsu so powerful it could rewrite a person's will without them even noticing. Plus, Shisui's high-speed body flicker, enhanced by Sharingan perception, was among the best in the Uchiha clan's history.

Normally, Mangekyō Sharingan users had two unique jutsu, one for each eye. But Shisui was a rare exception. Both his eyes used Kotoamatsukami. The only real mystery was whether the ability would reset after one use or if he could fire it off twice before waiting for a cooldown.

Still, Shinji had to hand it to the system. It had solved his biggest issue without him lifting a finger. Ever since he'd left the House of Evolution, he'd been worrying about how to awaken the Eternal form. Obito had no blood relatives alive, and the Eternal Mangekyō was supposed to require a transplant from a close relative.

Technically, Obito and Shisui weren't siblings, only distantly related through clan bloodlines. The fusion should not have been possible. But the system had overridden the genetics and simply forced compatibility.

"Alright then... Let's see what this looks like."

With a thought, Shinji summoned the new Mangekyō Sharingan into his hand.

The eye gleamed with a familiar pattern, sharp, pointed, and unmistakably shaped like a shuriken—Shisui's eye.

Not sure what the correct method was, Shinji went for the obvious solution. He pressed the new pair into his sockets, hoping instinct and system mechanics would take care of the rest.

To his surprise, there was no pain at all.

A blink later, the fusion process was completed.

The intricate Kamui spirals merged with Shisui's shuriken design, forming a new, more complex Eternal pattern.

Immediately, Shinji opened his system panel to check the update.

---

[Host: Shinji]

[Age: 20]

[Status: Human, A-Class Rank 5]

[Abilities: Dual Kamui, Kotoamatsukami, Susanoo, Flying Thunder God Technique, Body Flicker (Shisui), Basic Body Flicker, Rasengan, Wood Clone]

[Weapon: Crimson Blade of Yoru]

[Physique: 588 (+20 from Hashirama Cells)]

[Points: 110]

[Point Shop (Lv1)]

---

Just as he expected, Kotoamatsukami and Shisui's Body Flicker were now part of his arsenal.

From today on, he no longer had to worry about the side effects of the Mangekyō. No more ocular fatigue, no risk of blindness. All his focus could now go into improving his physical body and increasing the compatibility and purity of the Hashirama cells inside him.

Those two upgrades would determine whether he could finally unlock Susanoo's final evolution, the Complete Body Susanoo.

Ding dong!

Right as Shinji was soaking in the rush of his new Eternal Mangekyō Sharingan, the doorbell suddenly rang, snapping him back to reality.

Genos, maybe?

Shinji figured it could be him. Vaccine Man had been glued to his console lately, locked in gaming marathons ever since he'd bought the thing. Unless specifically summoned, the guy rarely showed up. So yeah, Genos seemed like the logical guess.

He strolled casually to the door and opened it.

But what greeted him wasn't the cyborg disciple.

It was a tall, striking woman with a commanding presence and the kind of beauty that made people turn their heads.

"You? What are you doing here?"

Shinji's pupils narrowed as he took in the sight. Standing before him, calm and collected, was none other than Blizzard of Hell, Fubuki.

"Not happy to see me?" she asked, lips curved in a soft, ambiguous smile.

Her tone caught him off guard. Compared to their last encounter, she was much more mellow now. The arrogance and guarded sharpness were gone. Instead, she spoke with a calm, almost pleasant demeanor.

"It's not that you're unwelcome…" Shinji replied, thinking back to Lily's messages. "Actually, I was planning to ask you something anyway. Come in."

Fubuki stepped inside and slipped off her heels at the door. This wasn't her usual domain, so indoor etiquette applied. With no slippers offered, she stepped onto the floor in sleek black stockings.

Her gaze moved around the apartment as she entered. Last time, she had barely looked around. Now, she examined everything with quiet curiosity. A modest living space, clean, compact, and far too ordinary for someone like Shinji. Especially considering the kind of people and monsters that revolved around this place: Genos, Saitama, Dragon-level threats…

It didn't add up. Why was a place like this the center of so much power?

But no matter how many times she scanned the room, she found no answers. It looked like any other apartment.

Shinji didn't seem to care about her confusion. He walked to the kitchen, brewed a cup of tea, and came back.

"Take a seat," he said.

"Thanks." Fubuki sat down across from him and casually reached for a bowl of snacks on the table, making herself comfortable like she belonged.

Shinji didn't bat an eye. He got straight to the point.

"Lily from your [Blizzard Group] told me everything. You added me to your little club without even asking me first, didn't you?"

Fubuki's hand froze mid-reach, her expression stiffening for the first time. There was a brief flicker of guilt in her eyes.

"…You found out already?" she asked, almost too calmly. "When did you even meet Lily? Why didn't I know?"

This wasn't how she wanted things to go.

She had planned to slowly build trust, approach Shinji herself, and win him over through her own effort and charisma. She was confident in her charm and leadership and thought she was handling things pretty well.

So when Lily had asked about it, she casually said, "Something like that."

After all, Lily was her most trusted subordinate. She hadn't expected her to go behind her back and tell Shinji everything.

Now she was stuck in a situation she hadn't prepared for. And it was getting awkward fast.

"We've known each other for days," Shinji said flatly. "But that's not the point. The real question is, you're still not giving up?"

"…I won't give up," Fubuki replied, her voice steady and serious. "I will recruit you into the [Blizzard Group], no matter what it takes."

"This isn't about what it takes," Shinji said, unfazed. "You don't have anything that would even tempt me in the first place. And I'm not refusing out of spite or some grand reason. I just don't want to. That's it."

He gave a small shrug. "If you didn't come here for anything else, I'd appreciate it if you leave soon."

"..."

Fubuki didn't respond. Her expression was hard to read, somewhere between thoughtful and slightly frustrated. But even with all that swirling in her head, her hand kept reaching for snacks like nothing had happened.

Shinji stood up and walked toward the balcony to hang the laundry. The washing cycle had finished a while ago, and he'd been putting it off.

When he came back inside, the living room looked almost untouched, except for one detail. Fubuki was still seated in the same spot, legs crossed elegantly, calmly snacking away.

Except now half the containers on the table were empty.

To be fair, it wasn't like he'd put out a huge spread, but still.

Shinji stared for a second. He wasn't the type to get petty over food, but this? This was definitely getting weird.

Was she really just here to eat?

Or had she already decided this place was some kind of casual hangout spot? Like she'd unofficially labeled it a friend's apartment she could drop by whenever she felt like it?