Welcome to chapter 17! The previous Extra Chapter was better received than I thought, so look forward to another one in the future! Right now, here's the main update:

"W-wait a minute," she groaned. "N-not so tight…"

"Geez, you're pathetic," Kuro sighed. "You're the one who came up with this idea in the first place, so bear with it."

"That was Ruby, not me!" Illya protested.

"Eh~ But I was merely acting upon Illya-san's own desires…" Ruby whined.

"Which part of that was my desire?!"

"Illya, don't fidget around so much," Miyu said, tightening the dress.

"S-sorry," Illya apologized feebly, keeping still and letting her carry on with her work.

"But, well, who would've thought the spell would work that well…" Ruby mused. "I guess this is what you would call a 'lucky mistake'?"

"Ugh… Spare me…" Illya sobbed.

"Okay, it's done," Miyu said. "How does it feel, Illya?"

"It's a little tight, but not uncomfortable," Illya replied, looking at herself in the mirror. "Thank you, Miyu!"

"Ooh, this is a surprisingly good sight!" Ruby said gleefully, flying about her tiny master. "Illya-san, is this your first time wearing a wedding dress?"

"Of course it is!" Illya exclaimed.

Dressed in a snow-white gown that flowed onto the floor, she could not physically make a grab for Ruby, so she settled for glaring daggers at the Mystic Code instead. She would have said something about the camera she somehow produced out of that small body of hers, if not for the camera Miyu of all people was holding in her hands.

"But is this really necessary?" Illya wondered aloud. "Just because Taig- I mean, just because Fujimura-sensei believed in Ruby's story… I-is it really necessary to have a mock wedding just to fool her?"

"Well, it's not like we can just conveniently erase memories whenever we want to," Ruby said, making a gesture for a shrug with her wings. Then, in a softer tone, she added, "Besides, it's more fun this way…"

"It's not fun for me…" Illya mumbled.

"I'll say," Kuro added. "If anything, I should be the one marrying onii-chan."

"H-he's not actually onii-chan!" Illya retorted, going beet red.

"Illya, that means rather than a proper relationship, you prefer actual in… cest…" Miyu pointed out, going pink in the face.

"T-that's not-" Illya's brain short-circuited at that, unable to believe she had just stepped on a landmine herself. "A-anyway! I-it's not like it's a real… w-wedding, so…"

"My, my…" Ruby said happily. "You say that, but aren't you happy about this? Proper or not, you still get to kiss Shirou-san don't you?"

"Ki-" Illya felt her brain short-circuit for the second time in ten seconds. The room was suddenly several hundred degrees too hot for comfort. She could not recall what she said in response to that, or if she even replied at all.

That had been hours ago. Or at least, it felt like hours ago. Right now, Illya was at the alter, standing face-to-face with her 'beloved', while hearing without listening to the priest Kotomine Kirei as he recited from the bible. It seemed to drag on and on, with not a single word registering in Illya's head because of the thoughts flooding her mind.

It-it's really happening, isn't it?! She thought. I-I guess I wanted something like this someday, but… Is this really okay?

"I-I do," Shirou stammered, snapping Illya out of her flustered thoughts. It did not take a genius to figure out that he was embarrassed as well.

"Very well," Kirei said blankly, closing the bible in his hands. "You may now kiss the bride."

Is that how this goes?! Illya thought. D-don't I have to say something as well?!

But Shirou was leaning in. He was bending forward to compensate for their difference in height, and his face. Was. Close. So close. Too close.

"Um, Illya?" Shirou whispered. "We have to finish this thing or Fuji-nee may get suspicious."

"Do you need any help?" Ruby asked cheekily in her ear, before abruptly pushing her head towards his-

Their lips met. A million thoughts swarmed Illya's head as she felt his lips on hers, setting her entire body on fire. A part of her body wanted to pull away, but her limbs were utterly frozen and her mind was a mess. All she could do in that position was stay there and focus on the… kiss.

Strangely enough, Shirou's lips were not warm. There was no heat in them, and they were not soft like flesh should be. Instead, she felt like she was kissing a piece of metal, like the flat end of a sword or something similar. But Shirou was a human, so why did he give off the vibe an inanimate object would…?

Unable to make sense of the bizarre phenomenon, she wrapped her arms around his neck, pulling him further into the kiss-

When she opened her eyes, Ruby was in her face. She was so close, in fact, that Illya's lips were planted solidly on the star embedded within the ring.

"Oh my, Illya-san…" Ruby said, sounding embarrassed. "I-if you were really into this sort of thing, you could always just discuss-"

Illya's scream went into ultrasonic.

"Must have been a nice dream, huh~?" Ruby teased, floating around her depressed Master. "Well, with one of my hidden functions, I can easily peek into Illya-san's memories and-"

"Don't! You! Dare!" Illya shouted, grabbing Ruby with both hands at a speed that would have impressed Lancer.

Ah… This is the worst… she thought as she wept. Ruby is teasing me both in real life and in my dreams… And… such a thing… of course it was a dream… There's no way s-something like that would… ever happen… and besides, there's no way Miyu would actually take photos of me like that...

"It must have been a very nice dream," Ruby commented, flying out of her grasp. "You wouldn't wake up even when I called out your name…"

"Ugh… Leave me alone…" Illya groaned."Wait a minute. Where's everyone?"

"At the dojo," Ruby replied. "Kuro-san mentioned something about helping Shirou-san train, so they should be sparring right about now."

"Eh? Kuro did?" Illya asked. "Why?"

"Who knows?" Ruby shrugged. "She said something about Shirou-san being the only one who could match Rin-san's Servant, and since she knew about his techniques…"

"Rin-san's Servant… Archer…-san, was it?" Illya recalled. "Now that I think about it… he wears the same clothes as the Kuro does, right? Does that mean they're the same Heroic Spirit?"

"It's very likely, yes," Ruby replied. "From what we've gathered so far, that held true for the Lancer and Saber cards, so it stands to reason the other Servants would correspond to the remaining cards as well."

"But even if that's the case, why would Shirou-san be the only one who can match him?" Illya wondered aloud. "Lancer-san and Saber-san aside, wouldn't Kuro have the best chance against him?"

"Well, it's only a hypothesis at this point, but…" Ruby trailed off, leaving the rest of her sentence hanging.

"But…?"

"Maybe it's so she can hog Shirou-san all to herself, don't you think?!" Ruby finished.

"Wha-"

Before Ruby could get in another word, Illya had already charged out the door.

The sharp crack of clashing shinais rang over and over, often followed by a grunt of pain from an auburn-haired boy. Contrary to what Ruby had said, Kuro and Shirou were actually training properly – much to Illya's relief. Even if Shirou was completely getting his ass kicked by the younger girl.

"Too slow!" Kuro scolded, sending Shirou's shinai flying out of reach.

"Darn," Shirou panted, tightening the grip on the remaining shinai in his other hand. "One more time!"

"… No, not quite," Kuro said, appraising him. "We've been at it for an hour but there's no improvement at all… This method clearly isn't working."

"Hold on, Kuro," Shirou insisted. "It's just been an hour; I can still-"

"We don't have the time," Kuro cut across him. "Now that we're going through with Caster's plan, you need to get stronger and fast. At this rate, we won't make it."

As much as he wanted to deny it, Shirou could not. The agreed upon time was tomorrow night, where they would raid Ryuudou Temple alongside Caster to rescue her Master. It was too soon (which could not be helped since rescuing someone was not something to be delayed), and as Kuro pointed out, at this rate he would just be a burden on the team. For him – someone who aspired to be a hero of justice – that was not acceptable by any means.

"You're right," he begrudgingly agreed. "But-"

"That's why we'll stop with using this method," Kuro cut across him, throwing away her shinai and instead producing the same pair of swords she and Archer favored. "Instead, we'll do things a little more… violently."

Shirou did not respond. He heard Kuro's words, and he indeed harbored questions, but the moment those swords appeared he stopped caring about anything else. He could not quite tell why, but the mere sight of those swords had rendered him spellbound.

They were nothing like Lancer's spear, which was very much like the spearman himself – wild, dangerous, and thirsting for the thrill of the hunt like a starving predator. They were nothing like the sword Miyu had – an exquisite blade full of pride and purpose despite clearly being a downgraded copy. Those swords in Kuro's hands held neither aspirations nor real purpose, and reflected neither pride nor aura. The craftsmanship of the blades was captivating, far more than anything he had seen in his life.

"Now, Shirou," Kuro said, getting into position. "I want you to produce these swords."

"Me? Produce those swords?" Shirou echoed. "That's impossible; I can't do anything except Reinforcement, and I'm not even that good with it."

"But the first type of magecraft you-" Kuro winced, as though something was hurting her. "w-was Projection, wasn't it?"

"Well, yeah," Shirou replied. "Wait; how do you know that?"

"That doesn't matter right now," Kuro insisted. "Just Project those swords and fight me. If you can't," she added, as Shirou opened his mouth to protest. "Then I guess you should just..."

Before those words registered in Shirou's head, Kuro had vanished. By the time he reacted to that, Kuro's voice came from behind him:

"… Die," she finished.

Throwing himself forward on reflex, Shirou felt the unmistakable sting of sharp metal as it tore through his shirt. Rolling away from his foe, he hastily got to his feet, strengthening the shinai in his hand as he did.

"Not a bad dodge," Kuro complimented. "But if you don't counterattack, you won't win, onii-chan."

A shiver ran down Shirou's spine. For an instant, he was reminded of the tiny girl who controlled that hulking bronze giant, and for the first time since they started training he could feel a truly dangerous vibe from the girl.

"Hold on, Kuro-" Saber began, but Lancer stopped her in her tracks with one hand. The other hand went to stopping Illya, who had jumped up in protest at the exact the same time. "Why do you stop me, Lancer?"

"Calm down, both of ya," he said. "She's indeed displaying some bloodlust, but she ain't out to kill the kid. As long as it doesn't get out of hand, just let it be."

"Lancer," Saber muttered. "Do you think that this will really help Shirou replicate Archer's swords?"

"Who knows," Lancer replied. "Modern magic is beyond me. However, the best way to get the kid accustomed to combat's to give him the feel of actual battle. And besides, that tanned ojou-chan does have a knack for mimicking that bastard, so it's probably safe to say she knows more about his techniques than we do."

"B-but, to put Shirou-san in danger like this…" Illya began.

"We're charging straight into the enemy stronghold," Lancer reminded her. "If he can't handle this much, he'll just get himself killed. Ain't that so, mini-Saber?"

"… Yes," Miyu agreed reluctantly. Logically speaking, Lancer was correct, but there were times even she did not like the logical answer.

Well, there's that, Lancer thought, but her moves are better than I thought. How did she lose that badly with her skills?

Having fought Archer once at the school, Lancer was more or less familiar with his abilities. Unless he had been holding back in that fight (which was quite possible considering that bastard), the bowman should not have overpowered Kuro like she and Saber had described. Differences in speed and strength aside, Archer and Kuro effectively fought with the same style, which reduced the overall difference in capability. When he had first fought Illya in her 'Lancer Install' form, he could tell that Illya was using his techniques, and if he applied the same logic to Kuro…

"Have you noticed it, Lancer?" Saber asked, noting the look in his eyes. "This is different from Illya's… 'Install' ability."

"You've fought Archer one-on-one before?" Lancer asked back.

"After the battle in the yard," Saber explained. "It was a brief exchange, and after that I had Kuro and Miyu fighting by my side, so I cannot say his attention was entirely on me in that battle."

"… We didn't actually do anything…" Miyu muttered under her breath.

"Kuro as she is right now is closer to Archer than Illya was to you or Miyu was to me," Saber went on, failing to catch Miyu's comment. "As for why that is, I cannot quite place it…"

"It's probably because of the Class Card inside Kuro," Miyu reasoned. "The Heroic Spirits within the Class Cards are most likely based off of the same Heroic Spirits in this Holy Grail War. It's likely because of that connection that Illya and I were able to glean your techniques during confrontation."

"A resonance between identical souls, you mean?" Saber asked, sounding awed at the thought. "Even if such a thing is possible, why is Kuro different from the two of you?"

"That's probably because of nee-san and myself," Sapphire spoke up. "When Illya-sama and Miyu-sama use Include, the two of us are able to become the medium for the Class Card and become the Noble Phantasm. However, in the case of Install, while we are still the medium for the Class Card, the user's body is also used for the pseudo-summon. The user dons the Heroic Spirit's abilities, and since these Spirits have more in common with a human soul than we Mystic Codes do, their memories are also 'downloaded' into the user via the Class Card due to the resonance that occurs. In-"

"Wait, Sapphire-chan!" Ruby said. "Leave the rest to me! I don't get enough serious lines these days, what with teasing Illya-san and all…"

"Hey, wait a min-" Illya began.

"Ahem. In Kuro-san's case," Ruby said, ignoring her master. "She does not have a Mystic Code to act as a medium. Instead, her entire existence is tied to the Archer card. She is the sole medium for the Heroic Spirit's power, and without the 'safety net' that is us Mystic Codes, she's likely to be more susceptible to the Card's influence. A larger spike in combat prowess isn't likely with a situation like hers."

"Does that mean she can get possessed by that bastard's soul?" Lancer asked.

No one replied to that. In truth, with the exception of Saber and Lancer, they all knew that Installing a Class Card without a Kaleidostick was indeed possible, and that the effects of doing so were far better, but that occurrence had been a phenomenon they were unable to explain even now. However, the real reason they did not want to bring it up was something else.

The one time Illya had Installed the Archer card without Ruby to defeat the Class Card Saber, it felt like the Heroic Spirit of the Bow was performing battle on its own. If such a thing was indeed the case, the implications on what could happen to Kuro were clear.

"Well then," Lancer said, getting to his feet as Saber did the same. "Let's go, munchkin."

"Eh? Where to?" Illya asked.

"Training," Lancer replied. "We Servants are always at the top of our game, but you guys can improve by sparring with us, right? Then let's not sit around wasting time."

"That is correct," Saber nodded, turning to Miyu. "We will be of no help to Shirou here, so let us go, Miyu."

"Understood," Miyu replied, casting a worried glance towards the boy barely keeping up with Kuro.

"Ah, right," Lancer said, as though he suddenly remembered something. "None of that 'Beast Mode' thing, 'kay?"

"As if I'd do that!" Illya screamed.

Shirou tightened the grip on his reinforced shinai, his breathing ragged and his clothes torn. Saber and the others had left, leaving him more room to dodge, but it also provided Kuro more angles to attack him from.

"You're recovering well," Kuro pointed out, as the smaller cuts started healing themselves. "Still not at his level of combat proficiency, though."

Shirou did not reply, being too busy trying to make sense of the situation. Every time he crossed blows with Kuro – or more specifically, every time their weapons touched – he felt his body become slightly more agile. The fatigue was not gone and the pain still lingered, but every time the tremors of impact shook his arm his movements improved after; without thinking, he could dodge better and without having to predict her moves, he could react to them. There was something about their weapons – or perhaps their magecraft – colliding that subconsciously improved his skills. But was such a thing even possible?

"You don't have the time to space out!" Kuro yelled, swinging her swords at him from the side.

Shirou could not react in time. Even with the improvements in agility, the fatigue on his body was weighing him down a great deal. Unable to properly parry the blow, he lost his shinai as Kuro knocked it cleanly out of his hands.

Without pausing, Kuro used the momentum of her swing to complete her turn, hacking away at Shirou's chest and drawing two streams of crimson in their wake. Gasping in pain and hastily backing away, Shirou attempted to dive for his shinai, only for Kuro to sink her knee squarely into his gut.

"Ugh!" Shirou grunted, falling to his knees.

What am I doing? Kuro thought, pausing in her thorough abuse of her older brother. What's gotten into me? Even if it's to help him, this is going too far!

I should have never become a hero.

The same words returned to her mind, howling inside her head and tearing at her brain. Regret, despair, anger – all the raging emotions that did not and should not belong to her – flooded her body and threatened to overwhelm her delicate frame.

Those ideals were not my own.

Shut up, Kuro snapped back in her head. This is my body, not yours! Get out of-

The man called Emiya Shirou… should not have lived.

When she picked up on the meaning of those words, Kuro's hand had already moved on their own; without obeying her will or caring about the man before her, her right hand lifted the sword of misty white.

"… Kuro…?" Shirou coughed, looking up at her.

"R-run," she croaked. But the killing intent pouring out of her being was real. Far more real than anything she had mustered before.

Disappear.

The blade descended. Shirou screamed. Blood sprayed into the air.

Streaks of light burst before Kuro's eyes as her sword shattered.

Instinctively, her left hand countered. However, before she could even complete half a swing, the black sword too was smashed into countless pieces.

Her right hand throbbed with a dull pain, from where Shirou had cut into in his attempt to deflect her blow. She could feel the blood trickling down her fingers and onto the dojo's floorboards, but she did not have the time to pay attention to that.

Panting from the effort, Shirou slightly relaxed his stance. In his hands, which had been empty before, now lay two beautiful swords – the exact same pair that Archer and Kuro had been so inclined towards. They were without a doubt the married swords Kanshou and Bakuya, and it was for the first time since she used them that Kuro thought they looked truly beautiful as they rested in his grip.

"T-that's it," she stammered, running past him and exiting the dojo without another word.

"Wait, Kuro-" Shirou began, but a sharp jolt of pain surged through his body and forced him back to his knees. Unable to maintain his grip on his weapons, he let go of them, and it took all of one second before they faded back into nothing. "Ugh! What on Earth…"

As someone who had trained himself physically, Shirou was no stranger to muscle pain due to excessive strain. He did not fancy himself the strongest man around, but he figured he had a higher threshold for pain than most. This, however, was on another level altogether.

"What… is this…?"

But the empty dojo offered him no answers.

"Ow… My body's still aching…"

Stepping out of the department store, Illya mumbled to herself. The training with Lancer had been tougher than expected, even if she did manage to improve from it. It was definitely not something she pictured proper Magical Girls would do, but if it helped her survive, she was not going to complain. Much.

I wonder how everyone else is doing, Illya thought to herself. Kuro had still been training with Shirou when she left the house, and Miyu had all but collapsed from training with Saber (who actually admitted she might have gone overboard). It made her somewhat glad that her sparring partner was Lancer instead.

"But was it really alright, Illya-san?" Ruby asked from inside her hair. "Wouldn't it have been better to have Lancer-san follow you?"

"There's no helping it," Illya sighed. "It's better if he's there to help Shirou-san with his training than out here shopping for dinner with me… Besides, I get the feeling Kuro's bothered by something lately… It'll be better if she has someone to help split the burden with."

"That's good and all, but what'll you do if an enemy attacks?" Ruby asked. She had not expected Illya to end up this far from the house, and even the Mystic Code was starting to worry a little for her master.

"It's alright," Illya replied. "There're plenty of people around, so they can't cause a ruckus in public, and I have the Command Spells with me, so it'll be alright!"

"Hmm? Where did all that enthusiasm come from?" Ruby asked. "Weren't you complaining like a geezer not too long ago?"

"Well… I just kind of realized…" Illya muttered, looking around. "Even though this place isn't home, it's still Fuyuki… So it's not as scary as I initially-"

The rest of the sentence died in her throat, and her entire body froze over in an instant. Almost as though time itself had stopped, Illya found herself immobile, unable to exert any force on her petrified limbs. Her throat would not obey, and even her eyes refused to turn. Just as her terrified mind tried to make sense of the situation, an extremely familiar voice froze the blood in her veins.

"Good evening," Illyasviel greeted from behind her.