Ten years ago, the Greater Grail summoned seven Servants and paired them with seven Masters, setting them against each other in a brutal war.
But something went terribly wrong.
The curses accumulated within the Grail overflowed, flooding not only Fuyuki City and Japan but the entire world. Flames raged across the globe for a full year, slaughtering humanity on a scale beyond imagination, until the survivors were forced to huddle within fortified base cities to cling to life.
This became known as the Great Calamity—a consensus across the magical world.Its root cause: the Fourth Holy Grail War.
The impact of that disaster was immeasurable. It overturned the international order, tore the magical world apart through repeated purges and reshuffling, and reshaped the Earth itself. Even the most devoted Type-Moon fans would never dare claim this world was familiar anymore.
And yet, in truth, the magical world had the means to contain the black mud if it had chosen to.
If magi across the globe had joined forces, they could have sealed the curse within Japan's borders. The black mud's spread was far slower than the Chaotic Tide of Tiamat; it took a full year to engulf the world. With sufficient will and sacrifice, containment was possible.
Indeed, when the black mud first erupted, that was exactly what magi attempted.
And they failed catastrophically.
The ones who shattered their resistance were none other than six corrupted Servants, born from the curse.
Those six were unstoppable. From the moment they emerged, they cut down magi like chaff, scattering every organized defense. They swept across the world with no opposition strong enough to stand in their way.
Thus, the black mud drowned the Earth.
In the years that followed, the corrupted Servants abandoned their global rampage and returned to Japan, roaming its wilderness.
Without exaggeration, outside of places like the Wandering Sea, Japan's countryside became the most dangerous place in the world.
Encounters with magical beasts or cursed spirits were already perilous—but stumbling upon a corrupted Servant meant certain disaster. Even dozens or hundreds of top-class magi together could not withstand the strike of a single corrupted Servant.
Why the six had all returned to Japan and lingered there for ten years was an unanswered question, debated endlessly.
Until now.
The mystery unraveled itself.
Because the Grail's power had never been exhausted. For ten years the Greater Grail had been gathering mana once more, and at last it had reached full capacity.
The Fifth Holy Grail War was imminent.
At such a pivotal moment, the return of five corrupted Servants to Fuyuki could mean only one thing.
"Another Holy Grail War…"
On Tōsaka Rin's steady face flickered a trace of irritation.
In this world, nearly everyone despised the Holy Grail Wars. Rin more than most. Her loathing ran so deep that words could scarcely capture it.
"You'd best start preparing yourself," Roy said with a wry smile, pointing to her hand.
There, burned into the back of her hand, were three crimson Command Seals.
The unmistakable proof that she had been chosen by the Greater Grail.
Roy had noticed them earlier in the Association's hall.
After all, the Greater Grail was built by the Three Founding Families—Tōsaka, Matō, and Einzbern. From the very beginning, its system had been designed to ensure at least one Master slot for each family.
At its core, the Grail was their tool to pursue the Root. Naturally, it prioritized its creators.
No matter how unwilling Rin might be, the Grail had forcibly etched the seals onto her hand.
After the three family slots, two positions were always reserved for the Mage's Association. The last two were left open for independent magi.
But in this Fifth War, matters were less predictable.
The Tōsaka and Einzbern families were guaranteed at least one slot each. The Matō family, however, was already in ruins. Matō Zouken was publicly dead, and Sakura remained in Misaki Town, not returned to Fuyuki.
Meanwhile, over two hundred magi—both freelancers and Association affiliates—were currently stationed in Fuyuki. Who the Grail would choose remained anyone's guess.
"Or are you planning to forfeit—hand your Command Seals over to someone else?" Roy's smile carried a teasing edge.
"Impossible!"
Rin stared down at the seals on her hand, her voice firm and unshakable.
"These Command Seals belong to me. I won't hand them to anyone. I'll use this Grail War to settle everything, once and for all!"
Seeing the resolute light in her eyes, Roy knew she had already made her decision long ago.
And it was fitting. Rin was fiercely independent—she had never needed anyone to steer her.
"Then get to preparing quickly," Roy advised. "The Association will uncover the truth soon enough. Right now you're one step ahead, but only one. Use that advantage—whether for securing authority or seizing victory in the Grail War."
"I understand. Thank you."
Rin suddenly gave a small, self-deprecating laugh.
"Thinking about it, I owe you so many debts I'll never repay them all."
"Then repay me with yourself." Roy chuckled.
"Wha—?! You—what are you saying all of a sudden?!"
Rin leapt back, fists raised, her cheeks flushed crimson.
"I'd also accept you as my servant."
Roy added the line with a cheerful grin.
"You really are…!"
Rin's anger deflated all at once, her shoulders slumping. The knot in her throat eased, leaving her sighing helplessly.
"I'll… think about it."
She brushed back her black hair, her face still pink as she turned to leave.
The Aozaki Residence.
"Lord Roy."
Roy had barely stepped through the door before Hayasaka Ai greeted him, a look on her face that clearly said she had something on her mind.
"What is it?"
He slipped off his coat and handed it to her.
"Do you want to return? But you haven't finished learning Utaha's maid training yet."
"No, that's not it."
Ai shook her head and pointed toward the living room.
"Someone's here… She says she's from the Aozaki family. Naturally, the barrier let her through. But neither I nor Utaha know her."
Someone from the Aozaki family… had returned?
Roy paused mid-step as Ai handed him his indoor slippers. Then his eyes lit up. Without hesitation, he strode quickly into the living room.
Inside, two figures awaited.
One was Kasumigaoka Utaha, dressed in a maid outfit with a modest lining, her long black hair spilling down her back.
The other was a striking woman with long orange-red hair tied back in a spirited ponytail. She wore the same black-rimmed glasses as Roy, her features soft yet dignified, carrying the refinement of a woman in her mid-twenties. Every movement radiated intelligence and maturity.
She wore a simple shirt and slacks—but Utaha instantly recognized the office suit she herself had been borrowing before.
Glancing down at her own chest, then back at the newcomer's, Utaha silently admitted defeat.