Aozaki Aoko Case File

The Aozaki sisters, after some bickering and playful exchanges, soared into the skies above the gates of the Winter Castle and gracefully landed in front of its entrance.

As soon as Aoko and Touko touched the ground, it was as if some detection mechanism had been triggered. From the pathways on either side of the gate, dozens of white-haired, red-eyed maids armed with cold weapons surged forth, glaring at them with predatory eyes.

"Tell Acht," Aoko said, tossing a letter to the maid at the forefront, "that the Fourth Magician has come to pay a visit."

The maid caught the letter floating mid-air, glanced at Aoko, and silently walked through a side door into the castle. Another maid seamlessly took her place, raising her weapon in vigilance toward Aoko and Touko.

After about twenty minutes, the lead maid returned to the gate, bowing toward Aoko and Touko with perfect precision. This time, she was unarmed. The other maids, seeing the head maid's posture, sheathed their weapons and formed two neat rows, clearing a path for the visitors.

"Please follow me," the head maid said.

"Acht-sama will see you."

Aoko and Touko followed the group of homunculi maids through the gates of the Winter Castle.

Upon entering, they were greeted by an opulent interior so lavishly decorated that Aoko briefly felt as though she had stepped into a royal palace.

Of course, the Einzbern family were no royalty, and this castle was no palace.

In the grand hall of the castle, elaborate crystal chandeliers emitted a cold light, casting heavy shadows from the towering walls onto the luxurious carpets below. The figures in the paintings on the walls seemed to stare at the visitors, creating an unsettling atmosphere.

Over the two-thousand-year history of this castle, they have conducted numerous renovations and reconstructions. However, since Makiri Zolgen and Justeaze had left the Winter Castle, the homunculi had made no stylistic changes to its design, merely maintaining and preserving its original grandeur.

Stepping across the finely polished marble floor, they ascended the central staircase to the second floor. Following the maids through a labyrinthine network of corridors, they eventually arrived at a conference room with enormous floor-to-ceiling windows. At the far end of the long table sat an elderly man, his hair and beard as white as snow, dressed in an ornate robe.

Seated on either side of him were two figures: a young woman who appeared to be in her twenties, a homunculus of the Einzbern lineage, and a middle-aged Japanese man in a black trench coat with an unkempt beard.

Emiya Kiritsugu?

Aoko smirked inwardly but showed no outward sign, calmly taking the seat opposite Acht. Touko sat beside her. (Though, due to her shorter stature, she looked rather adorable sitting there.)

"So, what brings the Fourth Magician to visit our Einzbern family?"

Jubstacheit von Einzbern inquired dryly.

"Why is there an outsider present in this discussion between Magus families?"

Aoko glanced dismissively at Emiya Kiritsugu, her voice cold and detached.

"Kiritsugu..." murmured Irisviel von Einzbern worriedly as she looked at her husband.

"He is merely a bodyguard I've hired," Acht explained.

"Given that we're dealing with a Magician, taking precautions is only prudent."

"Ara~"

Aoko laughed as if she'd just heard a joke.

"Are you serious, Mr. Acht? Even if every homunculus in your castle charged at me together with this mercenary, none of you could even scratch me. What's the point of having him here?"

"...Leave us," Acht ordered after a moment of thought. Kiritsugu glanced at his wife and then at Aoko before rising and leaving the room.

He recognized the reality of the situation: as the heir of a Magus family, he was fully aware of what kind of monstrous beings Magicians were. Although Kiritsugu was a famed magus killer, he was utterly outclassed against a wielder of the Five True Magics.

"I've come here to propose a collaboration," Aoko began after Kiritsugu had exited the room.

"I need all your documentation on the construction of both the Greater and Lesser Grails, as well as the Command Seal system."

"Impossible," Acht immediately rejected her request.

"Those are the foundation of the Einzbern family's existence."

"Don't be so quick to refuse," Aoko said playfully.

"At least hear the terms of our offer."

"No matter the terms, we will never relinquish the secrets of the Holy Grail War ritual," Acht declared firmly.

"I advised you to leave."

"Is that so?"

Aoko remarked, scrutinizing the artificial intelligence disguised as an old man.

"Not even a part of the Third Magic?"

For the first time since the Aozaki sisters entered the room, Acht's expression wavered.

"...Are you serious, Fourth Magician?"

Acht's voice trembled slightly.

"Isn't it said that each Magician can only master one Magic?"

"As the Fourth Magician, I do not need to deceive you," Aoko replied. "And my sister is a Grand-ranked Magus certified by the Clock Tower."

"...Moreover, you misunderstand, Mr. Acht," Aoko added.

"It's not that I've mastered part of the Third Magic, but rather that my sister's research has achieved a portion of it. She can flawlessly replicate a soul."

As someone deeply familiar with the details of the Third Magic, Acht knew that replicating a soul was extraordinarily close to the essence of materializing the soul—the core of the Third Magic.

"How can you prove this?"

Acht asked eagerly.

"If you can prove it and help us achieve our millennia-long wish, everything the Einzbern possess will be at your disposal!"

"Just lend us your alchemy laboratory," Touko interjected.

"I can replicate the soul and body of any one of your homunculi, provided there are sufficient magical materials and equipment."

"No problem!"

Acht exclaimed, rising to his feet.

"I will make the arrangements immediately! Irisviel, come with me to the underground alchemy lab!"

"Please, this way," Acht said, his tone now deferential, as he personally opened the conference room door for Aoko.