Digression
Emiya Shirou is a Hero of Justice. This is the phrase that describes him, in totality - a wandering soldier of fortune, who acts without thinking to save as many lives as possible. He trekked all across the world, involving himself in conflicts that he ought to have had no interest in. In the end, after making a contract with Alaya, the will of humanity, which would trap him in a hell of bloodstained servitude after his death - he was betrayed, scapegoated for crimes he did not commit, and hanged as a criminal.
Why would he make such a decision? What tragic distortion of his character led him to such measures? The answer lies in the Fuyuki Holy Grail War. In the fourth war, which saw the death of his birth family, and his adoption by Emiya Kiritsugu. In the fifth war, which saw him grow leaps and bounds in the power of his unique projection magecraft, and first catch the interest of Alaya.
From both cases, he gained crippling survivors' guilt, which mixed with his envy towards the joyful smile he saw upon the face of Emiya Kiritsugu to produce a distorted soul of steel, who sought only the salvation of others, in order to fill the gaping hole in his heart.
-But those are the records of the Archer summoned in Fuyuki. The Fuyuki Holy Grail War took place only once (or perhaps thrice, if one counts singularities) in this world; Emiya Shirou did not lose his family in the Fuyuki Fire of 1994, as there was no such conflagration. How, then, did the man in front of Natsuki Subaru come to be Emiya Shirou?
…Simply put, his family died of unrelated circumstances. An incident involving one of the cursed blades of Senji Muramasa, resolved by the wandering Magus Killer Emiya Kiritsugu. Though young Shirou's family along with many others, lost their lives, the boy demonstrated some degree of potential in magecraft. Kiritsugu, in a twisted sense of duty, took him on as a protege, much as his own teacher had done to him.
The sheath of King Arthur, [Avalon], obviously appears nowhere in this story. It was not embedded in the boy's body in the Fuyuki Fire, and did not reforge his soul into the shape of a sword. How, then did this Emiya Shirou come to acquire the unique projection magecraft of Emiya Shirou, and the reality marble called [Unlimited Blade Works]? The answer is simple.
He did not. The Emiya Shirou of this world possesses no such capabilities. His magecraft is almost completely divorced from that of the Archer who shares his name. His Element is [Steel]. His Origin is [Fire]. Though his projections, when he creates them, still have the same quirks of his other self, based on the same misunderstanding of his father's teachings - the complexity of even a Mystic Code is beyond his abilities to copy. His trump cards are wholly different, and much less troublesome, than those of Fuyuki's Archer - thus, the odds of Natsuki Subaru connecting the two individuals are close to zero. Indeed, the tanned skin, bleached hair, and steel-gray eyes of Counter Guardian EMIYA will never manifest in this man.
As for why this man was called forth, instead of that one - that hack of a narrator would likely claim that recasts are dull, but that would be a lie. In truth his motivation is most likely to avoid the troublesome presence of [Rule Breaker], a Noble Phantasm stored within EMIYA's Reality Marble that would unmake his whole pathetic stage the moment the man made use of it!
…Returning to the tale of Emiya Shirou, let us speak a little bit about his life that followed. In the leadup to the Fuyuki Holy Grail War, Emiya Kiritsugu was able to kill the Einzbern master and steal both her command spells and catalyst. With these assets, as well as other Command Spells acquired from one Atram Galiast, Kiritsugu and Shirou entered the war, as the masters of Assassin and Saber respectively.
They were promptly killed, along with all of the other masters, by Marisbury Animusphere and his servant.
Of course, although I say he was killed, Emiya Shirou did not die - his catalyst, [Avalon], permitted his improbable survival. Although Shirou considered taking revenge for some time, the intercession of Francois Prelati - reuniting Emiya Maiya with her biological son in exchange for the Emiyas' nonintervention with the establishment of Chaldea - smoothed things over. Ultimately, a war was a war, and the surviving Emiyas believed that Kiritsugu would have agreed with Marisbury's objectives, if not at the price of his own wish.
Emiya Shirou did not, however, agree to such an extent that he would join the organization of his father's killer - and so from that point onwards, the course of his life largely converges with that of Fuyuki's Archer. There is, however, one extra difference, pertaining to his Origin and Element - the fire of an oven or stove, and the metal of a cookery pan…
That is to say, the Emiya Shirou of this world is slightly more talented in the kitchen than the man who became Counter Guardian EMIYA.
…As for the servant he has summoned, I can find no justification for her existence other than perhaps the presence of strange, inexplicable particles.
***
Act 3, Scene 5
As I recover from my sudden stupidity-induced brain failure, I consider the situation. Aside from Emiya-senpai's skill in the kitchen, I don't really know much about his abilities. He's competent enough in combat that Flat-senpai and Professor Velvet trusted him to single-handedly guard me from Lars von Krudik while the man was still at large, so he's at least in the upper middle ranks of mages. But that doesn't really tell me anything of what he can do, since all he really did while he was guarding me was give me some impromptu cooking lessons.
His Servant, on the other hand… well, it's Arthur. She'll yell [Excalibur] and Excaliblast all over us, and if that doesn't work, she'll launch herself around like a rocket with [Mana Burst] until we're dead.
Yeah, we lose in a fight. Cooking competition it is - what do I know about Mysterious Impartial Judge X's favorite foods?
…!
"Alright, for the rules, we'll each cook three dishes - Western food, Chinese food, and Japanese," Emiya-senpai starts, but I cut him off.
"Hang on, Emiya-senpai. You're the challenger here, so shouldn't I have the right to decide some of the details of the competition?" I ask. "Besides, we're in a hurry, so Micchan and I don't really have time to cook three full dishes."
He strokes his chin thoughtfully. "...Yeah, I guess that would be fair-"
"Alright, let's make mashed potatoes!" I shout in triumph, and watch as Arthur's eyes narrow to pinpricks. Emiya-senpai opens his mouth to protest, doubtless to say that mashed potatoes can by no means be considered a meal - but before he can even say anything, his servant starts to scream.
"NoooOOOO! I don't wanna, I don't wanna, I don't wanna-!" She screams, rolling on the ground like a child. "Not the cafeteria food, not again! I thought I was free of Space Gawaaaaaiiiin!"
"S-saber!? What-?" Emiya-senpai turns towards her - alright, it's our win. Grabbing a baffled-looking Miyako by the hand, we promptly slip out the door while they're busy. This is how one wins a cooking contest against Emiya-senpai, after all!
"Well, I suppose fleeing was also an option," Says Recorder - for some reason his voice sounds irritated, like someone who just wasted a ton of effort.
"Is this really going to be okay?" Miyako asks as we run full speed, winding through alleyways to avoid the inevitable pursuit.
"I have no idea, but if whoever the enemy is wants to stop us from meeting up with Romani, I'm going to give everything I've got to do it!" I say. I'm stubborn like that!
Another few turns leads us to a main road - and then I hear it. Over the sound of our heavy footfalls, over the noise of distant car horns, but just below the overwhelming volume of Shaula's shots, still blasting away into the distance as they were before we slept.
Clack.
[Emergency Evade] - twice over. I fling Miyako and I to opposite sides of the road - but a splatter of blood tells me I was too late. Miyako hits the ground on the other side and does not rise.
And the blood-stained, one-armed tengu - tosses the red liquid off of his blade with a quick motion, as his cold eyes fall upon me again.