"So this is Emiya Shirou, huh?"

"She was an alternative version of Illya-san all along?"

Da'vinci and Mash exchanged words, observing the servant materializing before their eyes through the radiant glow of the summoning circle.

They observed from the control room as Ritsuka attempted to engage in conversation with the newly summoned servant.

Mash, intrigued by the unfolding scene, spoke with curiosity, "Could be she's some kind of legendary figure or a god-like being who took Illya's body as a vessel?" she suggested, glancing at Da Vinci for confirmation.

Da Vinci, however, furrowed her brows as she analyzed the data scrolling before her. "It's a possibility, but something doesn't add up," she remarked, her gaze fixed on the emerging servant. "Look at her name. Why does this servant bear an Emiya as a surname?"

"If I remember correctly, Illya-san's father was an Emiya, right?" Mash said, tilting her head to one side in wonder.

"That would mean she is truly just an alternative version of Illya-san, who bore her father's surname and a completely different first name."

"I see. Well, we can just ask her directly and find out."

"Yeah."

Their attention refocused on the summoning room, and an unexpected sight unfolded.

"Hm? Senpai is pulling something from his pocket."

"W-Wait, is that..."

With widened eyes, they observed as Ritsuka extracted a pair of pink panties.

Mash stammered, "Hold on, aren't those the same panties that were floating in the summoning circle a moment ago?"
Da Vinci raised an eyebrow, her eyes narrowing in amusement. "It seems they belonged to this servant after all... Could this be the reason the summoner device activated spontaneously? She flat-out came here just to retrieve her panties?"

Da Vinci observed as the little girl servant's face reddened, extending her hand, helplessly asking for her panties back, but...

"W-What is he doing? Why is he refusing to give her panties back?"

"Hehehe... Again..."

"Again?"

Da Vinci repeated in confusion as she glanced at Mash beside her. The aura around the kind-hearted girl shifted as she laughed in defeat, her eyes hollow.

"I don't know where I missed, but Senpai ends up taking up a hobby where he starts to collect his servant's panties for a collection. He collects about 71 out of 113 servant panties, and all of them are technically female servants..."

(Technically? And how does she know how many he has?)

Da Vinci wondered, her hands raised in an attempt to console Mash but not quite knowing how.

"You know what's worse..."

(There is still something worse?)

"He didn't get mine even though I gave him so many opportunities. He kept ignoring them. I even left one in his room, but he gave it back to me with a proud smile... He even managed to collect Astolfo's panties, so why am I excluded?"

Mash collapsed on her knees, tears streaming down her face, leaving Da Vinci's gaze going back and forth between her and the Master in the summoning room, who was waving the little girl's panties in the air with a dumb smile.

"When did those two go that badly downhill?" Da'Vinci wondered in confusion yet hopelessness.

Taking a deep breath, she refocused on the magical screen displaying the servant's stats.

True Name: Emiya Shirou

Personal Information:

Species: Pseudo-Servant, Homunculus, Magus, Magical Girl

Gender: Female

Height: 133cm

Weight: 34kg

Likes: Housework

Dislikes: Herself, Immature ideals

Talents: Housework

Class: Caster

Alignment: Neutral ・ Balanced

Parameters:

Strength: C+

Endurance: A 

Agility: C+ 

Mana: EX 

Luck: E 

NP: EX

Class Skills:

Independent Action: B

Allows independence for a short period of time even without a Master. However, support from the Master is necessary for extended battles.

Magic Resistance: C+

Grants protection against magical effects. Shirou possesses a moderate level of Magic Resistance.

Infinite Mana Supply: C

A literally infinite supply of magic energy from the Kaleidostick. However, due to the output being restrained by the user's own Magic Circuit's ability, Shirou is still yet to be able to show the stick's original power.

Personal Skills:

Cheerful Model Mystic Code: A

The self-proclaimed Ruby-chan, Formal name "Magical Ruby."It is made by the old geezer sorcerer of the jewel. Within the sorcery stick dwells a natural man-made spirit. Unnaturally obsessed with magical girls; although it supports its user, it stubbornly refuses to accept things other than magical girls. As long as it's having fun, everything's fine. So, cheerful-type. 

Mind's Eye (True): B

Capable of calm analysis of battle conditions even when in danger and deduces an appropriate course of action after considering all possibilities to escape from a predicament.

Magecraft: C+

Capable of using orthodox Thaumaturgy, such as Reinforcement to temporarily increase the essence of the tool and Projection to grasp the structure of the substance and temporarily replicate it. Before becoming a Heroic Spirit, even Reinforcement was quite difficult. However, the Projection sorcery she wields is quite special, as it is able to duplicate weapons, including all the components, to near perfection. In addition, during duplication, she can even read the wielder's skills, which allows her to gain all kinds of Noble Phantasms and combat skills.

Projection Magecraft: A

Ability to create physical objects, a duplicate objects.

Only when the target of projection falls under the category of "sword", does the Rank rapidly jump up to A+.

Trace On: Circuit Connection: EX

Upgrade from Projection Magecraft

Exceptional ability to connect to magical circuits and trace their essence.

Shining into the Future: A

Upgrade from Child of Nature

A Skill that represents one as a child born on the Reverse Side of the World that will eventually become the same. Even if they are not naturally occurring life, but living things created by human hands, sometimes even they can receive great blessings from the World.

Emotional Freezing: B

While she is a girl who smiles innocently, her thoughts can sometimes become like that of a cold-hearted demon, and her mental state can wielded as a weapon. The heart of ice may sometimes become a sword, or it may sometimes become a shield.

Noble Phantasms:

Unlimited Blade Work:

Type: Unknown
Rank: E~A++
Description: A reality marble that allows the user to project and create weapons. 

It is a high-class magecraft that embodies the user's internal worlds and imprints them upon the World as a Bounded Field for a short amount of time. It is their one true specialization of magecraft, the result of the concept of swords being both their Origin and their Elemental Affinity, and the basis of their Projection and Reinforcement skills. It is the definite ability obtained by someone whose life was saved by a sword, actually merged and lived with a sword, and acted as a sword all of their life.

Eternal Blaze Quintessence:

Type: Unknown
Rank: EX
Description: A powerful and mysterious Noble Phantasm with the highest rank. Its true nature and abilities are shrouded in mystery as the user herself is not aware of it.

Da Vinci raised an intrigued eyebrow as she continued studying Emiya Shirou's profile.

"She... has Emiya Archer's reality marble? It's not a surprise she has similar Personal skills to the Illya we know, but she also shares some Personal skills with Emiya Archer."

As she pondered yet before she could delve deeper into her thoughts, the automatic doors of the room opened with a soft whoosh. Turning around, Da Vinci was met with the sight of Emiya Archer standing there, holding a tray of sandwiches.

"Hey, Da Vinci. I noticed my Master skipped lunch, so I thought I'd bring him some sandwiches to eat... Did I come in at the wrong time?"

Emiya Archer raised an eyebrow, glancing at the chaos before his eyes.

"I can't really tell if your timing is perfect or not."

Approaching the collapsed Mash, Emiya Archer asked, "Your senpai?"

Mash nodded, still sniffling.

"Number 3...6?"

"13..."

"Oh, the panties hobby problem? I thought he dropped that hobby after I talked to him last time."

As they exchanged Encrypted chats, Da Vinci stood there, growing even more confused, wondering if the day could get any stranger.

Not long after, as Archer helped Mash to her feet, he took a curious glance through the glass toward the summoning room.

"Oh? Another von Einzbern? Her hair is different, though."

Da Vinci, now recovering from the unexpected situation, regained her composure and started to explain.

"Well, she's rather unique, if I may say."

"Unique?"

"Take a look." Da Vinci offered him the magical screen displaying the servant's stats. "She doesn't bear the von Einzbern surname. Rather, she has the Emiya one—"

"...Emiya...Shirou..."

"Y-Yeah."

Archer interrupted her with a Rather harsher voice than his casual one, though Da Vinci decided to just ignore that and continue her explanation.

"We're assuming she may be from an alternate world where she bears her father's name instead of her moth—"

"EMIYA SHIROU..."

"Yeah, that's her name...OH WOW!"

Da Vinci instinctively took several steps away, sensing the danger emanating from him. The man's face turned an alarming shade of red, and veins bulged on his forehead.
"E-Emiya-san?" Mash called out, concern etched on her face.

Da Vinci, not accustomed to seeing such a reaction from the usually composed Archer, took an extra cautious step back. "Uh, did we hit a nerve or something?"

Emiya Archer clenched his fists, his voice strained as he struggled to maintain composure. "Emiya Shirou... That idiot has no right..."

"Whoa, easy there, Archer," Da Vinci said, trying to de-escalate the situation. "We're just trying to figure out why this version of Illya has the Emiya surname. It's not like she—"

"I don't care about his surname!" he snapped, his tone cutting through the air like a blade. "Why is he even here?!"

(He?)

Mash took a step back, sensing the rising tension. "Emiya-san, we just summoned her..."

The Archer's eyes darted between the magical screen displaying Emiya Shirou's information and the summoning room.

"Forget it, I'll take my answer straight up from the source" He took a step forward, determination etched across his face. Without waiting for any further explanation, Emiya Archer pushed open the door to the summoning room.

Inside, Ritsuka stood, still holding the pink panties in his hand, completely unaware of the storm that was about to unfold. Emiya Archer's sudden entrance caught his attention.

"Archer? What's going on?" Ritsuka asked, perplexed by the tense aura around the man.

Emiya Archer didn't waste any time. His eyes locked onto Emiya Shirou, The embarrassed expression Shirou just held a moment ago disappeared Immediately, though her hand was still outstretched for her panties.

Withdrawing them slowly, she adjusted her posture, her face Rather become emotionless.

"I didn't expect to see you here, Archer," she stated calmly.

 "So it's really you!"

Ritsuka, still oblivious to the underlying tension, attempted to intervene. "Archer, she just got summoned here like any other servant. Why are you so angry? Do you know her?"

Archer shot a sharp look at Ritsuka, his eyes narrowing. "This has nothing to do with you, Master. I'd appreciate it if you stepped aside. The matter is between me and him."

"Ah..."

(I've never seen him this angry before. What's going on with him?)

"NOW..." He turned his eyes back toward the little magical girl, "Trace on!"

"I see...So that's how you want it...Trace...ON!"

As the two servants repeated the incantation, a magical projection materialized in both their hands – "married" twin swords, Kanshou and Bakuya.

As they did, the alarms around the place blared, "An increase of Magical Energy has been observed near Chaldea!"

"Emiya! Stop! What are you planning to do!?"

"We repeat! All servants in combat, unarm yourselves at once." 

"Forgive me, Master, but if you want me to stop, you'll have to kill me."

"What are you talking about—"

"Now you've done it, Alaya... You've chosen this path again... ", He directed his speech to the girl in front of him, "...No, you are being chosen, huh..."

"...You may be right..."

The battle between the two Emiyas unfolded within a matter of fragments of a second. Archer lunged toward her, and Shirou pushed Ritsuka away from their way.

Their swords met, and in the next moment, a shockwave was sent throughout the room.

Ritsuka, now on his butt, raised both his arms instinctively to protect himself from the shockwave, but nothing seemed to come.

"Huh?"

Opening his eyes slowly, he found Mash had already armed her large shield, protecting him from the clash between the two servants.

"Are you okay, Senpai?"

"Y-Yeah... I guess."
Mash helped Ritsuka to his feet, her eyes still fixed on the intense clash between Emiya Archer and Emiya Shirou. The two swordsmen exchanged blows, each strike sending shockwaves through the summoning room.

"Senpai, we need to do something! Their battle could damage Chaldea!" Mash exclaimed, gripping her shield tightly.

Ritsuka nodded, realizing the urgency of the situation.

Meanwhile, Emiya Archer and Emiya Shirou continued their intense clash, each trying to overpower the other with their swordsmanship.

"You've grown stronger, huh?" Archer taunted.

"I wish I could say the same about you," Shirou responded.

"Tch..."

Their swords moved in a blur, leaving afterimages in the air. The summoning room transformed into a chaotic battlefield, with swords materializing and disappearing with every swift strike.

Archer lunged forward, bringing Kanshou down in a powerful overhead strike. Shirou adeptly parried the attack, skillfully pushing Archer back.

Not allowing Archer to regain his composure, Shirou swiftly closed the distance, throwing Kanshou at him in a spinning motion.

Dodging the projectile with a subtle tilt of his head, Archer blocked the forceful upward swing of Bakuya from Shirou with one arm. 

The creak of the two swords rubbing against each other mixed with the loud alarm siren of Chaldea as the two fixed their eyes on each other.

"GO TO HELL!"

With a powerful push, Archer sent Shirou a few meters away, their eyes still locked.

"..."

Allowing the Kanshou in his right arm to shatter like thin glass, Archer slowly raised his arm behind his head, catching Shirou's returning Kanshou.

Taking a swift look at her Kanshou, then shifting his gaze back to the young girl, Archer questioned, "Is that really your strategy to win against me? One projection?"

"One projection?" She smirked at him, "Who said it's just one?"

As she spoke, Archer's eyes widened, and he instinctively scanned his surroundings for any potential threat, but...

"...??"

There was nothing. Confused, he returned his gaze toward Shirou.

"Pfff...."

She stifled her laugh at the last moment, locking eyes with him,

"You really are pathetic, you know that? Did you really lose trust in your senses just because the enemy used such a cheap trick? I genuinely feel sorry for you..."

"Y-YOU..."

ignoring the angry man in front of her and with a satisfied smile, Shirou took a quick glance behind him, noticing her master was about to use the command seals to stop them.

(It's about time Huh...)

She thought as she dropped her hands, watching Archer, angrier than ever, launching himself at her. 

With a small lift of her head, she allowed the twin blades to break into thin glass.

Archer's eyes widened as he watched the scene unfold, but he gritted his teeth, determined not to hesitate in continuing his attack.

"Don't you dare... Don't even think I would hesitate..."

However, as his blades were about an inch away from the little girl's head, they stopped.

It wasn't from the command seals, as Ritsuka hadn't used them yet, and it wasn't Shirou who blocked the attack—clearly, no hidden power was involved in the case.

It was simply, yet not really...

"Even if the body is without her soul..."

Shirou murmured, yet her voice was clear to his ears.

His hand trembled with every word from her mouth, attempting to end the girl's life by any means but he seemed to struggle to do so.

"You can't hurt her, even if she's not here, huh..."

A simple brotherly love for his sister was the straightforward answer to the situation.

"It doesn't matter how many people I've met; you remain the most cowardly being I know..."

Archer slowly withdrew his hand, turning away as he walked.

"...finally, something we agree on..."

As Archer distanced himself from the confrontation, the tension in the summoning room lingered like an unspoken echo. Shirou, still holding the broken remains of Bakuya in her hand, watched his back as he left.

The loud alarm siren of Chaldea continued to wail, a harsh reminder of the urgency surrounding them.

Ritsuka, who had been observing the intense exchange, finally stepped forward, his gaze shifting between Shirou and the departing Archer. "What just happened?"

Shirou sighed, her shoulders slumping as she attempted to gather herself. "Long story but..." She extended her free hand toward him. "I am ready to tell you everything in detail if you return my panties back, what do you think?"

"..."

He remained silent for a second, his eyes shifting from her open palm to the pink panties between his fingers.

"Do you know what... I suddenly lost interest in your long story..."

"..."

---