"Confirming body temperature... confirming the five senses... Just as I can objectively understand, I will speak my name aloud...
"Mash... Mash Kyrielight."
In another world, at Chaldea, the Organization for the Preservation of Human Order and humanity's last bastion, Mash woke up just as she always did.
Several months had passed since the light of humanity's future was extinguished, since the familiar Professor Lev caused a massive explosion in Chaldea, leaving the rookie Ritsuka Fujimaru as the only available Master. In that time, she and this new Master had overcome five major Singularities together.
Oh, right. What is a Singularity?
Past, present, and future exist simultaneously. The key nodes in human history are fixed and immutable; otherwise, the Human Order would be incinerated, and humanity's future would vanish.
A Singularity is an immutable node where a major anomaly has occurred.
Of course, the Singularities Chaldea had to repair were not naturally occurring. They were artificially created by the Demon God King Goetia, who dispatched Demon God Pillars to cause them.
Nearly all the Singularities Chaldea had repaired so far had been of this nature.
Ding-dong.
The doorbell rang. It was her trusted Senpai, reminding her to gather in the Command Room.
"Senpai, I'll be right there!"
In her pure white room, various souvenirs and fresh flowers were displayed, as if the artificial human known as Mash Kyrielight was gradually being filled with memories, developing a humanity uniquely her own.
As she answered, Mash continued to comb her slightly split-ended, neck-length pink hair. She slowly removed the non-prescription glasses she had started wearing after becoming a Demi-Servant.
"Haaaah!"
Crossing her hands above her head, she stretched backward with a deep exhale. The movement caused the fabric of her black miniskirt to tighten slightly as the gentle curves of her chest became more pronounced.
With that single response and a long stretch, Mash Kyrielight was fully revitalized.
She bent over, pulling on a pair of black tights under her miniskirt. Just before leaving, she grabbed the short work jacket from the head of her bed.
When she opened the metal hatch door and met the gaze of the orange-haired girl waiting outside, she flashed her brightest smile.
"Good morning, Senpai!"
"Good morning, Mash!"
The girl's lower half was dressed similarly to Mash's—a miniskirt and black tights—while her upper body was clad in the white Chaldea Master uniform, which resembled a straitjacket.
They met, smiled, and exchanged greetings. Then, the Master named Ritsuka buried her face in Mash's chest, forcefully inhaling the fresh, clean scent of her "little eggplant."
Helpless and flustered, but long accustomed to it, Mash Kyrielight knew her Master was just this kind of playful person.
But before Ritsuka could finish her antics, a broadcast crackled to life, urging them to hurry. It was Dr. Romani, Chaldea's current director.
Several months ago, a massive explosion caused by Professor Lev had left Chaldea with only Ritsuka as a viable Master and had killed nearly two hundred staff members. As a result, Dr. Romani now held the highest position.
Initially, many had doubted his capabilities, but now they were on the verge of tackling the Sixth Singularity.
"Alright, the Singularity we're targeting this time is located in Jerusalem, in the year 1237 AD.
"Historically, this was when the Ninth Crusade failed, and the Church lost its influence over Jerusalem. The Holy City in the Middle East instantly became a powder keg of conflict among various factions.
"But don't worry—Da Vinci-chan will be joining you on this exploration. Miss Magi☆Mari also sent me a message saying she'll provide Chaldea with extra support for this mission."
With orange hair, a green shirt, and a white lab coat, the man had a gentle, almost gullible-looking face. This was Dr. Romani Archaman, Chaldea's current director, known simply as Dr. Romani.
However, only one Servant in Chaldea currently knew the truth: this gullible-looking man was none other than the Servant summoned by the Former Director in this world's Fourth Holy Grail War.
His true identity was the King of Mages, Solomon, the pinnacle of all Mages.
But after the Fourth Holy Grail War, he had wished to become human. As long as he chose not to wear his crown, he was a truly ordinary mortal.
And as an ordinary human, he genuinely loved humanity. To reclaim its future, he worked himself to exhaustion day after day, having not slept well in a very long time.
But...
"Doctor, we know you're under a lot of stress, and it's normal to chat with a virtual idol every night, but please don't take her reassurances seriously!"
Because they didn't know Dr. Romani's true identity, ordinary Chaldea staff members felt free to tease him. They meant no harm; their underlying message was simply a wish for him to get more rest.
"Ahem! What virtual idol? Magi☆Mari is real! Anyway, once you reach this Singularity, you'll definitely receive extra support. That's what Magi☆Mari told me."
"Yeah, yeah, yeah..."
Even Ritsuka was just humoring him now. Only Mash and Da Vinci-chan were listening seriously.
But after the commotion in the Command Room subsided, they all knew this exploration would be fraught with difficulty...
Mash Kyrielight and Ritsuka Fujimaru—one a seemingly ordinary, fragile homunculus, the other a completely normal human—lay down in the Spiritron Transfer Device as naturally as ever.
This device enabled time travel, and it was precisely because so few could withstand such journeys that Ritsuka Fujimaru was humanity's last Master.
Mash, as a Demi-Servant, could use the device through a loophole. Da Vinci-chan, being a Servant herself, had no issues with it.
When Chaldea first designed the Spiritron Transfer Device, they had anticipated that Mages transferred would only have their physical bodies, lacking any means of defense. Thus, Servants were essential as their armed escorts.
The device sealed shut, the countdown began, and the familiar rollercoaster-like sensation washed over them.
Meanwhile, far away, outside the tower where this world's Merlin had secluded himself...
As an endless sea of flowers swayed, Merlin personally completed a Servant summoning. A golden-haired young woman slowly materialized within the crimson Magic Circle.
Avalon rejected Guinevere, denying her soul refuge within its borders. Because of this, during the summoning process, the King of Knights—who should have been summoned alongside her—was forced to relinquish her own body, offering it to Guinevere as a "shell."
"Lia's face, a Ruler-class container... I get it! I'm Jeanne d'Arc!"
As the light of the Magic Circle faded, Merlin's jaw dropped wide enough to swallow a goose egg. Before him stood a figure with Artoria's face but dressed in unfamiliar attire.
Her first words only deepened his shock. Even though this world's Merlin was far less emotionally expressive than his other-world counterpart, he couldn't help but press a hand to his forehead, wondering if accepting help from another world had been the right decision.
"Whatever. Well then... hello, Miss Guinevere."
"Hello, Merlin. Should I say 'nice to meet you for the first time,' or 'long time no see'?"
She wore an incredibly ornate nun's habit. Perhaps because their destination was Jerusalem, Guinevere had been summoned in her Ruler aspect.
This manifestation was based on her historical feat of purging the Great Britain Church, an act that had brought about the Purification Plan ahead of its time.