The Hakuryuukou The Strongest DxD

In the universe of *Jujutsu Kaisen*, there existed a technique considered the pinnacle of sorcery.

It was called [Domain Expansion].

The ultimate technique was a barrier ability that manifested a person's [Innate Domain].

An [Innate Domain] is a metaphysical territory that exists within the mind of its creator.

Domains can only be manifested using vast amounts of energy. This can alter entire areas into the user's domain. However, domains created with pure energy without a barrier technique or an imbued innate technique are considered incomplete.

[Domain Expansion] is the most supreme ability of any jujutsu user.

It allows them to realize their [Innate Domain] by casting a barrier to create a separate space and using energy to construct an environment within it. The target is trapped within the barrier, and the domain is completed once it fully incorporates the user's innate technique.

A signature hand sign or another type of unique signal specific to the user is required to activate [Domain Expansion].

In essence, [Domain Expansion] is "an environment constructed with energy and manifested through a cursed technique."

In theory, Alexandre would be capable of creating his domain. The problem was that he lacked a cursed technique.

Without it, his domain wouldn't have the primary advantage of [Domain Expansion]—all attacks performed within the technique have absolute accuracy.

[Cursed Techniques] are intrinsic supernatural powers congenitally engraved in a sorcerer at birth.

They typically manifest around five or six years of age and are entirely unique to the respective user.

These techniques cannot be copied in most cases because they require innate talent to possess. For those who have an innate technique, it accounts for 80% of their skill set.

In short, a [Cursed Technique] is essentially something hereditary, like a clan's genetic ability.

And Alexandre Ikuse did not possess one, so he could never use a [Domain Expansion].

However, the young Ikuse hadn't let that stop him. His ability to deconstruct and analyze all techniques circumvented his problems.

With knowledge of [Cursed Techniques], Alexandre only needed to deconstruct and reconstruct them for his own use.

With this, he was able to recreate jujutsu, including recreating the main techniques of Ryomen Sukuna—[Cleave] and [Dismantle].

A man whose genius was unmatched, Alexandre's [Cursed Technique] was never the same, constantly changing based on his desires.

"Domain Expansion…"

Alexandre Ikuse's voice came out as a whisper as the space around him shifted.

Before Augusta's eyes, something astonishing was happening as the entire space transformed.

The place they were in was unbelievable.

It was an enormous hall. The design of the vast hall was simple but artistically crafted.

It had a mysterious and fantastical feel. But what would truly catch anyone's attention was the environment.

There were thousands of books and ingredients moving in and out of their shelves on their own. Even some shelves were reorganizing themselves.

The semi-translucent marble floor was solid, but the constantly shifting pattern was moving. And most interestingly, the movement of everything followed the rhythm of the music playing loudly in the background.

And at the center of it all was a giant platform where Alexandre Ikuse stood.

The scene was a work of art.

"The Domain of God."

A [Cursed Technique] in constant flux, capable of adapting to any situation, thus allowing Alexandre to freely modify it based on his desires.

Modifying it was obviously not simple. The act of deconstructing and reconstructing the formulas behind the ability would take years even for talented magicians.

The act of doing so in mere seconds only showcased the overwhelming power and talent of that man.

"What is this…"

"A barrier created from my technique, where all my abilities are enhanced. You can think of it as being inside my mind, where all my knowledge is stored."

The teenager's golden eyes focused on the trembling witch.

There was something there, veiled behind that facade of joy in the boy, an overwhelming desire consuming him from within as it drove him toward what he sought.

Then she saw something…

"What?!"

It was there, something that wasn't there a moment ago, tainting the pure white of that immense hall with its presence.

It was something behind Alexandre Ikuse, something that looked like an immense gate, its height likely around five meters.

It had a demonic appearance, carved in a gold-like material, and where its doors should have been, there appeared to be hundreds of thousands of souls, all distorted and demonic in appearance.

Looking at those distorted souls was an invitation to test one's own sanity, one's own mind seeming to be slowly consumed.

"Ah, I see, so you can finally see it… no, it's precisely because you're in my domain that you can see it," Alexandre smiled cheerfully. "This is one of my two Grimoires. I recommend not looking at it for too long. Even very powerful people have gone mad after staring at it for a while."

The witch's eyes widened as she averted her gaze.

"Very well, then I'll deal with you."

A single finger of Alexandre's was raised, pointing directly at Augusta.

"Absolute Cancel."

[Domain Expansion] guaranteed the absolute accuracy of the user's supreme technique.

Since he didn't have something that could be called that, Alexandre's domain was different.

If he used, for example, [Divide!], he wouldn't even need to touch his opponent when inside the domain.

Thus, all magic performed within the [Domain Expansion] had absolute accuracy.

[Absolute Cancel] could completely erase the existence of a spell, but it required touching the spell or the user, and within the [Domain Expansion], all enemies were within his reach.

The possession spell that had affected Lavinia vanished as the young Ice Princess's body fell unconscious to the ground.

Augusta's original body slowly reformed, while a smile spread across Alexandre's lips.

A single book shot from the shelf toward the sky above Alexandre, and as the book opened, dozens of formulas began to fire from it.

Alex's smile widened.

"Domain Expansion - Malevolent Shrine."

The [Domain of God] was an expansion capable of adapting to any technique Alexandre Ikuse used, freely modifying itself according to the technique he employed.

As someone who found his strength not in raw power but in the diversity of abilities and spells, this was the [Domain Expansion] that suited him best.

Within the book that modified the domain was the knowledge of the techniques of the being called "Sukuna," so the domain adapted to it.

The barrier slowly dissolved, but the domain remained.

It was a truly divine technique, as the ability to realize the innate domain without using a barrier is akin to an artist drawing in the air instead of on a canvas.

By allowing an escape route with the barrier's removal, a new capability is formed, granting Alexandre a vast range of effect.

With a maximum range of 500 meters.

Even Sukuna had only a 200-meter range. The ability to enhance even another [Domain Expansion]—all of this was within the [Domain of God].

Anything with energy within range—[Cleave].

For inanimate objects—[Dismantle].

Until the [Malevolent Shrine] ended, it would attack all targets within range with guaranteed accuracy.

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From the area of effect of the [Domain Expansion], for those observing, everything within a 500-meter radius was covered by a malevolent aura.

The two types of cutting attacks—[Cleave], which adapted to the target's energy to cut them in one go, and [Dismantle], used on inanimate objects—were executed automatically by the technique. Everything within its range was struck with absolute precision.

The trees, the rocks, the mountains—everything within the range was hit.

When the effect of the [Domain Expansion] finally dissipated, the entire 500-meter radius was reduced to pure dust, as that was all that remained of those struck by the demonic technique.

Despite the overwhelming power of his [Domain Expansion], it wasn't omnipotent. Those with vast amounts of magical energy could resist its effects.

Alexandre's golden eyes slowly moved toward where Augusta's body should have been, now completely shredded and turned to dust.

The Witch of the Purple Flames didn't even have time to comprehend what happened to her before dying.

But Alexandre's attention was elsewhere, on a small amount of purple flames floating above where Augusta's body should have been.

Unlike other Longinus that only transferred to a new wielder upon the current one's death, [Incinerate Anthem] could move freely from one wielder to another.

When a Sacred Gear's wielder dies, it is sent to the heavens and automatically redistributed by God's System, but [Incinerate Anthem] didn't do that, moving freely.

The young mage slowly approached the flames, extending his right hand.

"That's mine!!!"

Alex's head turned toward the voice, seeing a blonde witch in gothic clothing approaching—Walburga, Augusta's disciple.

She must have stayed far enough away to avoid being caught in the [Domain Expansion]'s effect or used teleportation to escape.

But…

"Cleave."

A single line, invisible to all but Alexandre, formed at Walburga's neck, and in the next second, her head was separated from her body.

Alex's eyes slowly turned back to the purple flame, and snapping his fingers, a magical purple cube appeared, trapping the [Incinerate Anthem] within it.

[Perfect Cube], a nearly impenetrable barrier spell originating from the world of *Seven Deadly Sins*.

As he stored the cube with his magic, Alexandre let out a sigh.

It seemed everything was finally over.

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Five days had passed since the events with Augusta and the members of the Utsusemi Agency.

With Satanael's death, which greatly surprised Alex upon learning it was Cao Cao's doing, the members of the Five Principal Clans managed to capture the Utsusemi Agency members.

Everyone was rescued, but what had happened couldn't be erased.

In one of the hospitals belonging to Grigori, Lavinia Reni was recovering from the damage caused by having her body stolen by Augusta.

In one of Grigori's rooms, the two Ikuse brothers stood.

"So, you're leaving?" Tobio asked, looking at Alexandre in front of him.

While Lavinia was in the hospital, the others were also recovering. Cao Cao was waiting for Alex outside while he spoke with his younger brother.

"Yeah, I came mainly because of you, Tobio, and now with everything resolved, I think it's time to go."

"Are you sure?" Tobio asked. "I'm certain there's a place for you here. No one would mind."

"I know," Alex gave a slight smile. "But I think each of us should walk on our own two feet. You have talent, Tobio. I don't want you or the others to become dependent on me. I'm sure you'll grow a lot at Grigori, but this place isn't for me."

"I understand," Tobio murmured sadly. "I hope it's a see you later, not a goodbye."

"What are you talking about?" Alex laughed. "We're brothers. When you need me, I'll come running to your side."

"The same goes for you. Whenever you need me, I'll be there."

The two brothers, despite rarely seeing each other, shared a strong familial bond and smiled at one another.

As he bid farewell, Alexandre left the room, and waiting for him outside was Cao Cao.

"So, where are we going?"

"An old acquaintance called asking for help, and I couldn't refuse, but before that, I have something to discuss with Azazel."

As he watched his adoptive brother disappear with a teleportation circle, Cao Cao sighed.

He suspected this acquaintance might be one of Alex's past 'lovers.' The Hakuryuukou had many 'acquaintances,' but those he considered 'friends' were very few.

If he excluded himself and Tobio Ikuse, who fit as part of Alexandre's family, there were only three people Cao Cao had seen Alex refer to as friends.

The little witch from the Golden Dawn and her brother, the wielder of the Holy Sword.

And the one Alexandre called his best friend—the Man Who Embodies God.

Recalling that man with a dark personality, Cao Cao shook his head. He really didn't know how Alex got along so well with him.

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In another part of Grigori…

Azazel was at his desk, slaving away over paperwork he'd been putting off for the last two weeks.

It wasn't his fault he got caught up in his Sacred Gear research or in various bars picking up girls!

His vice-governor-general, Shemhazai, dragged him here and told him to finish everything under penalty of death. Needless to say, such a threat lit a proverbial fire under his ass, and he'd been here for the last eight hours and accomplished nothing! Surely, this was his punishment for sleeping with a human and falling.

But seriously, how was he supposed to resist those breasts?!

Lamenting how unfair the world was, he certainly didn't scream like a little girl when a voice said "Yo" right in front of him.

No!

He'd deny that until the day he died.

He jumped up, his wings spreading from his back, scattering his piles of paperwork, and two spears of light formed in his hands as he looked toward where the voice came from in his office.

The problem for Azazel was that he hadn't sensed him enter!

Emerging slowly from the darkness of the room was Alexandre, with his usual smile.

"Jeez, kid, don't scare me like that," Azazel grumbled, eliciting a laugh from the teenager.

The fact that Tobio Ikuse's brother could sneak in like that—he should've expected it from someone who managed to stay hidden from the supernatural world for most of his life.

"And well, [Dimension Lost] definitely has something to do with it," Azazel thought internally.

"Don't worry about it, Azazel," Alex said, smiling. "I just came to say I'm heading out."

"Seriously?" The purple eyes of Grigori's leader blinked slowly.

He already knew he couldn't keep this kid by his side. It was dangerous to let two powerful Longinus wielders run loose, but at the same time, Azazel also knew Alexandre would never harm his younger brother.

The fact that Tobio stayed with Grigori was a way to keep in contact with the White Dragon Emperor.

"So, where are you going?"

"I have some things to take care of, but first, I got a request from an acquaintance, and I'm going to check it out."

"I'm heading to Kyoto now."

Azazel's eyes narrowed. Kyoto was home to the Youkai Faction, closely tied to the Japanese Gods.

"For someone who doesn't like getting involved with factions, you have some very important friends," Azazel commented, earning a smile from Alex.

"Connections are important," Alex said, smiling. "I just came to say goodbye and deliver something."

Azazel watched as Alexandre summoned a small orange book and handed it to him.

"What's this?"

"I've recently become a writer. This is my first book, released a few days ago. I thought I'd give you a copy. Let me know your opinion later."

With those words, the Hakuryuukou vanished again with his teleportation magic.

Azazel's eyes slowly turned to the book: "The Wise Frog? Must be his pseudonym… I wonder if there's a reason for it."

The Governor-General's eyes finally landed on the book's cover.

*Icha Icha Paradise - Valkyrie Edition*.

Seeing his massive piles of papers, Azazel thought they could wait a bit.

Something told him this book would be interesting.