Shunko

"Now that's incredible..."

"That tiny ninjutsu released enough water to fill a lake."

"Just how much did you compress your chakra?"

Looking at the forest before them, completely destroyed, and the vast lake that had appeared out of nowhere, even Demon couldn't help marveling at the power of Yu's ultimate Water Release.

"You're back, Demon."

Hearing the voice he hadn't heard in so long, Yu smiled.

"Hmph. Don't give me that cheeky smile."

"I'm still mad about what happened last time."

Demon poured cold water on Yu's excitement.

"You're still mad about that...?"

Hearing the deliberately cold tone in Demon's voice, Yu scratched his head sheepishly. Then a curious look appeared on his face. "But now that you mention it, I really would like to see what you look like when you're angry..."

Ever since the Demon inside him awakened, Yu had imagined what she looked like more than once.

Judging by Demon's alluring, bewitching voice, Yu imagined her as a voluptuous beauty with a bust of at least 36E, seductive features, and a gaze so captivating that it could leave anyone spellbound.

"Hmm? Why do I get the feeling..."

Demon seemed to sense what Yu was thinking. Her charming voice turned suspicious. "You seem to be thinking about something rather inappropriate."

"Ahem... Well..."

Coming back to himself, Yu gave an awkward little cough. "I hope you won't get too angry when you see it..."

"Because I'm developing another technique, one even more dangerous than Hard Vortex Water Blade."

As he spoke, Yu began training. He took off his haori, revealing the sleeveless undershirt beneath it.

"What are you up to now?!"

Demon jumped at the sight, a bad feeling rising in her heart.

"Boom!!"

Before Demon could react, a huge burst of chakra erupted from Yu.

No, rather than chakra, it was a mass of highly compressed ninjutsu exploding violently.

"Rumble..."

As the highly compressed ninjutsu erupted from Yu,

violent whirlwinds formed around each of his arms, instantly pulverizing every rock on the ground nearby.

At last, a pair of dazzling white lightning wings took shape, clinging to Yu's shoulders and back.

"What is that?!"

"Yu! What's happening to your strength?!"

Demon's voice trembled with disbelief at the sudden burst of power from Yu.

Since she existed inside him, Demon could clearly sense that Yu's strength had increased tenfold in an instant.

It was unlike any ninjutsu in the Naruto World and unlike any Devil Fruit in the One Piece World. She had never seen a power like it.

"This tremendous power... Could it be complete?"

"An ultimate technique on par with the Eight Inner Gates..."

With white lightning coiling around his back and shoulders, Yu felt the power within him multiplying without end and widened his eyes.

He had no doubt that one punch could shatter everything in front of him.

"No, that's not right..."

"This level of amplification is nowhere near the Gate of Death."

But when he thought of the terrifying power Might Guy had unleashed in the original story by opening the Gate of Death—dozens or even hundreds of times greater than that of the Five Kage—Yu shook his head, still unsatisfied. "It seems I'm nowhere near finishing it."

"Are you crazy?!"

"Stop it right now!!"

Demon had no idea what new technique Yu was developing, but sensing the power in his body multiplying and running wild, she shouted anxiously in his ear.

"Boom!!"

But it was too late.

As his strength continued to multiply, the highly compressed ninjutsu around Yu's back and shoulders hadn't stabilized. The white lightning coiling around him finally exploded, blasting him through the air like a cannonball.

"Crash! Crash!"

After breaking through two trees, Yu finally hit the ground in a heap, his entire back covered in gruesome wounds.

Yin Healing Wound Destruction!!

But Yu seemed to have been prepared for this. Supported by his powerful chakra, the injuries on his back healed at a visible rate.

It was one of the advanced Medical Ninjutsu Yu had mastered. Before being struck, he accurately judged where the blow would land and quickly concentrated a certain amount of chakra there. Afterward, the wound would heal rapidly on its own.

"As expected, it still failed..."

"Good thing I was prepared. I nearly died."

Yu lay on the ground for more than ten minutes before the serious injuries on his back had completely healed.

That dangerous new forbidden technique—yes, it was Shunko from Bleach.

Over the past three months,

apart from treating injured shinobi in the Konoha Medical Corps, Yu had spent all his remaining time in the Hokage's office studying ninjutsu scrolls and training.

He had occasionally asked the Third Hokage for advice as well, and his ninjutsu skills had improved by leaps and bounds.

His chakra reserves and level had also continued to rise, which gave Yu the idea of developing a new technique.

The Eight Inner Gates were known to everyone as an advanced form of Taijutsu in the Naruto World. Opening all eight gates removed every restriction on the human body, a technique also called the Gate of Death. Once activated, it granted power dozens or even hundreds of times greater than that of the Five Kage.

In the original story, Might Guy opened the Gate of Death and unleashed such power that he briefly overwhelmed and thrashed Uchiha Madara in his Six Paths form.

But the price was that the body rapidly withered and died. Even with Yin–Yang Release to keep him alive, Guy was left permanently crippled.

Shunko, on the other hand, was the ultimate combat technique in Bleach, combining Kido and Hakuda.

The user's back and shoulders were enveloped in highly compressed Kido. Explosions made the Kido and the user's limbs work as one in battle.

Once activated, it could increase the user's combat strength tenfold, or even several dozen times, giving every movement immense destructive power.

So Yu had wondered: if Shunko in Bleach could combine Kido and Hakuda, could he try combining ninjutsu and Taijutsu from the Naruto World to create a forbidden technique on par with the Eight Inner Gates, but with far fewer side effects?

After studying a vast amount of ninjutsu, Yu had finally succeeded.

Even the incomplete Shunko could increase his physical strength tenfold.

But judging by its current extremely dangerous and unstable state, it was nowhere near suitable for use in battle.

"It seems there's no way I can finish this technique anytime soon..."

Looking at the nearly obliterated forest around him, his clothes in tatters, his body a complete mess, and his chakra completely drained, Yu couldn't help giving a wry smile.