Fuyuki City, Japan.
The first Holy Grail War occurred in 1832, and until the third war in 1944 after the second, Holy Grail Wars took place in Fuyuki. However, during the third Holy Grail War, a magus hiding among the Nazis managed to shake off Matou Zouken, steal the Grail, go to Romania, and lie low.
And to divert the attention drawn to the Grail, he spread the method of creating Grails and the Holy Grail War system, causing numerous Subcategory Holy Grail Wars to occur.
Because of this, he quietly researched the Grail for several decades.
And once his research was complete, he declared insulation and independence from the Clock Tower, aiming for the Grail's completion. The low-ranking magi from the Clock Tower, who tried to stop Romania's Yggdmillennia from creating a new faction using the Greater Grail, were already annihilated by the Lancer summoned by the Grail.
However, a magus who luckily survived reached a hidden Grail and activated the three families' emergency system, created in case the Grail was stolen. This system was the Makiri's special contingency plan to additionally add seven Servants and seven Masters in case all Servants summoned for the Holy Grail War sided together. It was a system prepared in case they, without being eliminated, used only the Grail to erase their long-cherished wish, the manifestation of the Third Magic.
Because of this, the Clock Tower put forward seven chosen Masters to stop Yggdmillennia, who aimed to become independent using the Grail. Hiring one person from the Church, one professor from the Clock Tower, and five freelance magi, their goal was to seize or destroy Yggdmillennia's Grail, and Yggdmillennia was also preparing to summon Servants in response.
And, the Grail summoned a Ruler to mediate this Great Holy Grail War. However...
In the past, a Ruler who survived the third Holy Grail War, the illegitimate result of Einzbern's deeds, existed in an incarnated state. Although incarnated, she was a Ruler summoned by a Grail. Therefore, the new Ruler could not properly manifest as a Servant, so she performed a possession summoning by choosing a vessel in France, the new Ruler's homeland.
She was supposed to be summoned in Trifas, Romania, but to make matters worse, the Ruler summoned in a human body was in a situation where she had to get to Trifas, Romania, by her own power.
Manifesting in the body of Laeticia, a student from the French countryside, and integrating into one with the personality of a girl who possessed a body, personality, and disposition similar to her own... seemingly not a reincarnation or descendant, the Ruler・Jeanne d'Arc was summoned.
She was at a loss about what to do from now on...
Paaaaa!!!
"This is..."
In front of such her, a boy was summoned.
It was a summoning not by the Grail but by a Counter Force... a Servant summoned to save the world. Jeanne d'Arc, who quickly received information from the Grail, welcomed the boy without wariness.
"Servant Ruler, Fergus mac Róich. I look forward to working with you? Ruler."
"Fergus mac Róich... the hero of Celtic mythology. You seem quite different from the information..."
"Hm? Ahh~ That's it. I understand. In a different sense, I'm a ruffian here, right? I am a Servant from a different worldline. Should I say I'm fundamentally different from the Fergus you know? As a prime example... Scáthach is my wife."
"Eh... It doesn't seem to be a lie, indeed. Understood. So such cases exist."
"Originally, that's the interesting part about heroic spirits~ I look forward to working with you as a fellow mediator, Ruler."
"Yes, I look forward to it, Ruler."
First, they decided to call each other not by name but by 'Ruler,' to get used to the term and prevent any accidental revelation of their True Names. While Jeanne gathered her luggage to go to Romania, Fergus left the house and looked around the surroundings.
"This is really... troublesome. Although I know everything, it's not like I can go and deal with him right away... Since I have to destroy the Grail anyway, I should keep quiet until the Grail is seized."
As someone who knows the entire story of the failed Great Holy Grail War, it was nothing but regrettable that he couldn't immediately go deal with Amakusa...
"It really takes a long time... Medb also took a long time for this kind of thing, right?"
A woman's preparations indeed take time. Medb also did a lot of preparation when going out somewhere. She could have just solved it with runes in the first place. In that sense, does she feel a bit inflexible? Being a student from the countryside, she probably doesn't have much money to spare, so I should prepare. Should I make some gems or gold coins first?
While waiting, I roughly made a bag of gems and a bag of gold coins. With primordial runes, making gold like legendary alchemy is a piece of cake. Money won't be a problem. There's a reason why I specifi~cally gave away that Key Sword. No, actually, I could make that Key Sword if I wanted... I think I might meet him later, and imagining the golden prick getting angry at me when he notices makes me think maybe I shouldn't...
No, since the worldline is different, it shouldn't be a problem, right?
"Did you wait long? There was a lot of luggage to pack..."
"No, it's fine. But, is that luggage homework?"
"Well, being a student and all... Haha. Well, shall we go? Ruler."
"Yes, let's depart, Ruler. To Trifas."
As Jeanne comes out, we decide to wait for the village bus first.
"... When will the bus come?"
"Probably... it will take about 30 minutes."
"To get to the city?"
"An hour?"
"... You know our Great Holy Grail War is in four days, right?"
"Th, that's true, sorry..."
"... Sorry. I'm going to use something now."
"?"
No, I see a future that takes too long. Even for me, there's a limit to flying to another country... Sorry, golden prick. Let me borrow your treasury for a bit. I remember the coordinates and password I calculated back then. I immediately make a counterfeit Key Sword and open the treasury.
Vwoooom...!
"A, airship...?"
"Not a fighter, I borrowed it."
"From whom?"
"From a king who died thousands of years ago. The dead have no say, right? So I didn't tell him I was borrowing it."
"Isn't this grave robbing?"
"So, you're not getting on?"
"... I'll get on."
I take out the Vimana, get on it right away, and let Jeanne board. Now... the controls are like this. Understood.
"But, won't this be detected?"
"It's not a shabby Noble Phantasm that can be observed by humans. It's the King of Heroes' personal vehicle, after all."
"Eh...?"
Kwaaaaaa!!!!!!!!!!!
"Kyaah!"
"You don't have to hold on tight, you won't fall off~"
I immediately fly to Romania at top speed. That King of Heroes' treasure, and I carve runes on it to increase the speed even more. It should arrive in a few minutes. As expected, incredible speed, AUO. Your plane is awesome. It's fun like a ride.
Thus, we arrive in Romania from France in just a few minutes. Arriving directly in Trifas would draw too much attention, so we arrive in Băilești, keeping some distance.
"Ugh... Do you ride this kind of thing... regularly?"
"No?"
"... Then let's not ride it next time."
"Hmm, understood."
Is this scary? Even a saint can't help it. A person is a person, after all? I immediately put away the Vimana, close the treasury, and erase the Key Sword. I'll use it later if there's a need.
"For today, let's stay here and slowly head to Trifas starting tomorrow~"
"To arrive in Romania this quickly..."
"Haha, the title of Great Hero isn't given for nothing, right?"
"A hero of myth, is it... Wait a moment, we need to exchange currency first. In Romania, unlike France, they use the Euro or the Romanian Leu."
"Yes, let's go exchange currency now. After that, we'll have a meal."
I take out the bag of gems and show it. Then Jeanne's eyes widen in surprise.
"Wh, what is this...?"
"Gems. Is it not enough?"
"No, no, there's too much!? Where did you get this!?"
"I made them? They're genuine. Using primordial runes, making them is a piece of cake."
"Primordial runes...? Are they different from regular runes?"
"The Grail doesn't give that level of knowledge, it seems. Well, those who use primordial runes can be counted on one hand, so it's natural, I guess. Anyway, put the wallet away. I'll take responsibility for the Ruler's finances. Despite how I look, I was the king of Ulster, you know?"
"Eh... Then, does that mean in your case, you didn't pass it on to Conchobar?"
"Roughly, yes. Then let's go right away. I've found the location of a jeweler with clairvoyance. Let's make the transaction immediately! Don't worry, they can't cheat me, so we'll get more than the fair price."
"Ah, yes..."
I immediately change into modern clothing and go with Jeanne to find the jeweler.
And we made a fortune. Making money is easy.
"Now, let's go eat something delicious. Is there any food you'd like?"
"... Just a minimal meal is enough. It's not my body, and if I only eat the proper daily amount..."
"How inflexible. Ruler, if you're worried about gaining weight, you can just exercise as much as you eat to lose it."
"Is, is that so?"
"... Among the people I know, there is someone similar to you. She loved to eat. You don't need to hold back either, Ruler."
"Is that so... For now, I understand. I'm also interested in modern food... Ruler, you seem to know the modern era well, and while I have Laeticia's knowledge, she's a country girl like me... Would it be okay if I asked for an escort?"
"An escort... Hmm, I'd rather decline, as I might get in trouble... Haha."
"Is that so..."
Whether it's Laeticia's influence or her own fantasy, she seems disappointed. But... you'll have to deal with the aftermath too, Jeanne. I take her to a famous restaurant in this city.
Her appetite is... as if proof that for her weight, she has a large chest, Jeanne rivals Artoria. She has the same weight as Marie Antoinette, but the reason her chest is so large is probably the difference in nutrition... And Laeticia said her chest is even bigger? The child will grow well. Laeticia herself is also a good eater.
"Gastronomically, I might fall into depravity..."
"How about cake for dessert? They say there's a good shop over there."
"... I'll go!"
Yeah, I like your honesty.