Crossover: The Problematic Deity of Arcadia

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After some time...

Dressed in ornate kimonos like mirrored black-and-white twins, Kagaya Ubuyashiki's children—Kiriya and Kanata—immediately dropped to their knees and bowed low.

"Kiriya Ubuyashiki, Kanata Ubuyashiki, along with the Demon Slayer Corps, humbly welcome Lord Ryo Yagami!"

As their voices rang out, a sea of kneeling figures followed, darkening the ground in unison.

Without hesitation, the support corps obeyed the command of their master's children, showing the utmost respect to their honored guest.

"Hm?"

Ryo raised an eyebrow at the sight, visibly surprised.

"Looks like Kanae went and spilled the beans to Kagaya Ubuyashiki after all."

Kiriya, still kneeling, bowed his head respectfully and explained, "Apologies, sir. Lady Kanae, the Flower Hashira, informed our father out of a sense of duty."

Kanata added immediately, "If this has displeased you in any way, we are prepared to offer seppuku as an apology."

Ryo chuckled, shaking his head.

"Oh, come on now. I'm not one of those petty evil gods who'd make adorable kids kill themselves over something this minor. That'd be way too much."

With that, he casually strolled up to the black-and-white twins and asked, "Do you have any ore for forging Nichirin Blades?"

"We do," Kanata replied, rising to her feet and clapping her hands twice.

From among the kneeling rows, several Kakushi rose swiftly and sprinted to a nearby building, returning moments later with large chests filled with glistening ore, panting from the weight.

Kanata stepped forward again, explaining, "These are the ores we've brought this time for the Corps members to select from. If you need more, we can request additional supplies from logistics."

Ryo glanced at the chest now set before him, reached out to touch the ore, and narrowed his eyes.

"This should be enough."

Kanata gave a slight nod, then continued, "As you requested, we've also gathered the various Breathing Styles. They're being sent to the Butterfly Mansion for you to examine."

"The Breathing Styles? Nah… I don't really need them anymore."

Still idly touching the ore, Ryo raised his head to glance at Shinobu before saying, "By observing Kanae and Shinobu's techniques, I've already figured them out."

He paused, then added with mild sarcasm, "Controlling your breathing rhythm to speed up blood flow, pushing the body beyond its limits in exchange for lifespan… Talk about a brute-force method."

Without waiting for Shinobu's reaction, Ryo tightened his grip and crushed the ore in his hand.

BOOM!

Fragments scattered with a brilliant red glow. Then, one by one, the ores in the chest lifted into the air, melting and merging. Before their eyes, a blade reminiscent of a Zanpakuto began forming in the red light.

The magic-like sight left the Demon Slayer Corps frozen in awe, eyes wide, breaths held.

In that moment, even those who had no idea who Ryo was finally understood why their master had insisted on giving him such reverence.

This was no ordinary man. His presence was godlike—maybe even demonic.

Ryo, now holding the freshly forged Nichirin Blade, narrowed his eyes again. From his pocket, he pulled out a pocket watch, flicked it open, and glanced at the dial.

"3, huh? Breathing Styles, Nichirin Blade, and now the Demon Slayer Corps. That brings the counter to three."

He was only nine points away from being able to bring the Demon Slayer World fully under the observation scope of the Little Garden.

And as for how to get those remaining nine points? Ryo had a pretty good idea.

With that thought in mind, he turned to Kanata. "Did Kagaya Ubuyashiki have anything else to say?"

Kanata bowed again and replied, "My father wrote that he has arrived at the Butterfly Mansion and is awaiting your audience."

Ryo smirked. "The Butterfly Mansion, huh? That saves me some effort."

Then, turning to Shinobu and Makomo, he said, "Let's go. Time to meet the leader of the Demon Slayer Corps."

"Understood!"

The two girls nodded in unison, a spark of curiosity glimmering in their eyes at the thought of meeting the elusive 'Master of the Demon Slayers.'

— — —

At the Butterfly Mansion – Living Room

In the guest room, Kagaya Ubuyashiki sat quietly, dressed in his black kimono. His frail body trembled with each cough as he looked toward Kanae apologetically.

"Forgive me, Flower Hashira. The contents of your letter were simply too important. I had no choice but to invoke your name when requesting a meeting."

"No need to apologize."

Kanae sat beside him, calmly pouring tea as she replied, "Honestly, I was more surprised you believed the nonsense I wrote in the first place."

She chuckled softly, almost in disbelief. "Otherworldly beings descending into this world… I didn't believe it myself. Yet I still wrote to you."

Kagaya gave a small shake of his head, eyes warm.

"To me, every member of the Demon Slayer Corps is like a child of mine. And a parent doesn't dismiss their child's words as mere fantasy."

He coughed again, then his voice grew a bit more animated. "Perhaps you don't know this, but the Ubuyashiki family… We've always had a peculiar ability."

"We can sometimes see glimpses of the future—an intuition born from subtle signs."

"When I read your letter, I saw a vision."

Kanae blinked, curious. "A vision? Of what?"

A faint smile played at Kagaya's lips as he spoke, almost dreamily,

"I saw myself surrounded by my children, all gathered around a warm fire, holding hands. And standing in front of us… was Muzan Kibutsuji, basking in the light of the sun."

"That's the future I saw."

Kanae was stunned—and more than a little hopeful. "T-That's… that's an incredible future to imagine."

"Yes." Kagaya chuckled through another cough. "A future where everyone is alive, where we face the morning sun together…"

"If I could witness that with my own eyes, I think I could die content."

"Please don't say such things," Kanae said quickly, her expression tightening. "Your health is vital to keeping the Corps running."

"It's alright," he replied gently. "Because maybe, by then, we won't even need the Demon Slayer Corps anymore."

Kanae looked troubled but didn't argue further.

After a pause, she asked in a quieter voice, "May I ask… in the vision you saw, was Ryo there?"

Kagaya's smile brightened.

"He's the one who brings that future."

Kanae blinked, momentarily stunned, but deep down, she couldn't deny it made sense. She whispered to herself, "True peace… So that's what it really looks like…"

Just then, a Kakushi entered the room, knelt, and announced,

"Master, Lord Ryo Yagami has returned to the Butterfly Mansion along with Shinobu and a probationary recruit."

Kagaya smiled as though the sun itself had arrived.

"The future we've been waiting for… has come."

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