I'm in a crossover anime world, and I've been transported to Hogwarts twice.

Hayasaka Ai stood beside her, her hand already on her hidden weapon, her eyes as wary as a cat with its fur standing on end.

Genichi Hanyu nodded frankly: "That's right. I need to have a good talk with the Demon Slayer Corps' leader, and you need an opportunity to prove your worth."

You're using us!

Hayasaka Ai said coldly.

It's just a mutually beneficial arrangement.

Genichi Hanyu shrugged.

Kaguya Shinomiya pursed her lips. She couldn't deny that she had at least contributed to this mission, which would give her some leverage when she returned to the Shinomiya family.

"Well then, let's get down to business."

Genichi Hanyu turned to Kagaya Ubuyashiki and said, "As you can see, I have the ability to destroy all demons, including Muzan, but I need the power of the Demon Slayer Corps."

Kagaya Ubuyashiki was silent for a moment, then slowly asked, "What do you want?"

"Join Chaldea."

Genichi Hanyu snapped his fingers, and a holographic projection appeared in the air, displaying a huge spherical facility, "an organization dedicated to saving humanity."

Countless images flashed across the projection screen: various vampires, various undead, and various monsters.

"Humanity's enemies are far more than Muzan Kibutsuji; there are many more disasters that are even more difficult to deal with than Muzan Kibutsuji."

Genichi Hanyu's voice turned serious: "Your Demon Slayer Corps will serve me, and in exchange, I will completely destroy Muzan Kibutsuji."

Kagaya Ubuyashiki closed his eyes, seemingly weighing the pros and cons.

In fact, he had already foreseen part of the future through his precognitive abilities: the Demon Slayer Corps would join Chaldea, and Muzan Kibutsuji would be destroyed.

"I can agree to that, but I cannot speak on behalf of the rest of the Demon Slayer Corps."

Finally, the head of the Demon Slayer Corps nodded solemnly, "I hope you will allow those who do not wish to continue fighting to withdraw, it is entirely up to them (Li Ma Zhao) to do so voluntarily."

"Are you kidding? If they're all unwilling, why should I even bother with this deal?"

Genichi Hanyu rolled his eyes. Did he think he was running a charity?

Shinobu Kocho wiped away her tears and was the first to step forward: "As long as we can eliminate Muzan and avenge my sister, I am willing to join the fight."

The other Pillars also expressed their willingness to join Chaldea as long as Muzan Kibutsuji could be defeated.

"Okay, then it's settled. The next step is..."

He turned to Kaguya Shinomiya and Ai Hayasaka: "Kaguya Shinomiya, Ai Hayasaka, what is your choice? Are you willing to join Chaldea?"

"Can we do that too?"

Kaguya Shinomiya and Ai Hayasaka naturally knew what Chaldea was—an organization that surpassed the United Nations.

"We join."

Kaguya Shinomiya answered quickly, and Ai Hayasaka followed suit, saying, "I'll join too."

74. A terrified Muzan, He Xi was actually...

Deep within the Infinity Castle, in a dark space where time seemed to stand still, Muzan Kibutsuji suddenly crushed the potion he was experimenting with.

Her crimson eyes, like congealed blood, suddenly lit up in the darkness, and her fingernails unconsciously scratched the armrest of the throne, sending splinters of wood falling.

"Doma is dead?"

This realization was like an ice pick piercing her spine.

Her slender fingers tightened suddenly, her sharp nails digging into her palm, and dark red blood trickled down her pale skin.

This is the first time in over a century that an upper moon has fallen.

Fragments of memory flooded into her mind through blood connections.

The last thing Doma saw was a human wearing strange goggles, holding a bizarre weapon that emitted a purple light.

"Damn it!"

Her red lips trembled slightly, and then she uttered a curse, freezing the air.

The surrounding candlelight flickered violently, casting a menacing shadow on her exquisite face.

Suddenly, a sharp, stabbing pain exploded from my temple.

Muzan clutched his forehead in agony as the images Doma transmitted before his death flashed through his mind: the man used some kind of transparent thread to cut Doma into pieces, then raised a device that emitted a purple light, and Doma was instantly burned to a crisp.

That's sunlight!

They actually imprisoned sunlight inside objects!

"Following the fate of the country."

Kibutsuji Muzan's pupils shrank to the size of pinpoints, as if the nightmare from hundreds of years ago had returned.

That swordsman with the 567th rank and the flower-patterned earrings, that blade of light that severed eternity.

Now, that feeling of trepidation is back.

She stood up abruptly, the dark patterns on her black kimono writhing as if alive.

Driven by the call of blood, the entire Infinite City began to twist and reorganize.

The walls writhed like internal organs, and the corridors stretched out like intestines.

Ten minutes later, the remaining twelve demon moons knelt in the blood-red hall.

"Dou Ma is dead!"

Kibutsuji Muzan said coldly.

Akaza was the first to look up, his pink tattoo standing out starkly against his pale face: "My lord, please allow me..."

"Shut up."

Kibutsuji Muzan's furious roar shook the entire space.

She walked slowly down the steps, her black kimono rustling as she walked, but paused almost imperceptibly as she passed Kokushibo.

This swordsman, the only one who has survived since the time of Yoriichi, is now bowing his head with all six eyes closed.

The jade pot emitted a soft clattering sound: "Oh dear, Master Doma actually..."

"all of you."

Muzan Kibutsuji's voice suddenly became eerily calm.

"Set off immediately, find that person, and tear him and every human being connected to him to pieces."

She paused for a moment and added, "Completely destroy that thing that emits sunlight."

As the Upper Moons withdrew, Muzan Kibutsuji suddenly called out to Kokushibo: "You stay."

After everyone else disappeared, Muzan Kibutsuji spoke up: "That thing that emitted purple light can simulate sunlight. We absolutely cannot let such a thing remain in this world."

Kokushibo's six eyes opened simultaneously, and the patterns of Upper Moon and One appeared on two of them.

"Just like Yoriichi Tsugikuni back then, they shouldn't exist in this world."

After Muzan Kibutsuji finished speaking, the entire Infinity Castle fell into dead silence.

……

The laboratory's ultraviolet disinfection lamps bathed everything in a cold blue light.

He Xi's white lab coat was stained with suspicious dark red stains as she intently adjusted the molecular model in the holographic projection in front of her.

On the virtual screen, the double-helix DNA is being eroded and recombined by some kind of red substance.

"Success?"

Genichi Hanyu's voice came from behind him. He was holding two cups of coffee and handed one to Tsurugi.

He Xi waved without turning her head, and the projection immediately split into more than a dozen sub-windows: "Look at this."

She pointed to a set of constantly changing data: "When the cells of the child are exposed to ultraviolet light, the nucleoproteins undergo irreversible denaturation."

Genichi Hanyu suddenly spoke up: "You used the computing power of the Great Clock?"

"if not?"

He Xi finally turned around, her eyes behind her glasses gleaming with the light of a mad scientist.

"With the equipment available today, it would take at least twenty years to analyze a ghost's cells."

She suddenly lowered her voice: "And I discovered something even more terrifying."

The safe under the lab bench slid open silently, and a test tube containing a dark red liquid slowly rose up.

The liquid shimmered with a mother-of-pearl-like luster under the light, and it seemed as if countless tiny points of light were moving inside.

"Based on Doma's blood sample, I deduced Muzan's original prescription."

He Xi lightly touched the test tube with her fingertips: "But it lacks the most crucial ingredient, the blue spider lily that can help ghosts overcome sunlight."

"drop!"

A sudden notification sound made Yuzuru Genichi look over, and then Yuzuru Genichi stared at He Xi.

Although Genichi Hanyu brought the Great Clock, the energy consumed by the Great Clock in this world is simply a bottomless pit.

Even with a mountain of nuclear reactors prepared as an energy source, it was still a drop in the ocean.

The energy meter on the monitor was flashing red numbers wildly, and Genichi Hanyu's heart ached as well.

He Xi's actions alone probably burned through hundreds of thousands of yuan worth of nuclear reactor energy.

"hiss!!"

He gasped, clutching his chest, feeling difficulty breathing.

"Don't make that face."

He Xi continued operating the instrument without looking up: "Once you figure this out, you'll definitely make a profit."

"Can't we wait until we get back to continue the research?"

Genichi Hanyu's voice was trembling.

He Xi finally turned around, pushed up her glasses and the lenses reflected a cold light: "Whether we can figure it out after we go back is unknown. Of course, we have to figure everything out while we're in this world now."

She suddenly leaned closer, her eyes gleaming with fanaticism: "I speculate that if a perfect demon doesn't have sunlight as a fatal weakness, it's practically immortal!"

"The legendary blood-dripping rebirth is an understatement!"

He Xi waved her arms excitedly, "It doesn't even need a drop of blood, just a little bit of residual skin tissue can regenerate indefinitely!"

Seeing He Xi's mad scientist-like appearance, Yu Shengxian's lips twitched.

He was filled with regret at that moment.

No one had ever told him that this seemingly elegant old aunt actually harbored the soul of such a mad scientist!

"correct."

He Xi suddenly spoke.

"Quickly send someone to find Tanjiro Kamado and make sure you get the Blue Spider Lily from him."

"Yes, yes, I understand."

Genichi Hanyu responded listlessly, feeling utterly exhausted.

"and many more!"

He Xi called him back, mysteriously opening a metal box, "When you go out, you can help me test my new toy."

The box contained dozens of arrows filled with purple liquid, which gleamed dangerously under the light.

"Wisteria poison?"

Genichi Hanyu raised an eyebrow.

"wrong!"

He Xi smugly wagged her index finger.

"It's a concentrated solution of wisteria flower toxin that I've purified and enhanced. Any low-level demon below the Twelve Ghost Moons will die instantly upon contact!"

"Even that old monster Muzan Kibutsuji might not be completely immune!"