"Amamiya, your girlfriend's here to see you!"
"So lovey-dovey first thing in the morning~ Just like a model couple~"
"Hahahaha!"
As soon as the bell rang, the classroom erupted with the boys' teasing laughter.
Shirou looked up and saw the unattainable beauty standing at the classroom door.
Rin Tohsaka of Class 1-A.
The young lady who lived in that enormous, luxurious Western-style mansion on the hillside, and an honor student to boot.
Beautiful, academically brilliant, and exceptionally athletic. She was practically perfect.
She was rational and polite, never arrogant despite her beauty, seemingly the embodiment of every man's ideal.
Naturally, someone like her was treated by the male students as an untouchable goddess.
Too perfect. Too far beyond their reach.
And this very Tohsaka-san was actually Shirou's passionately devoted girlfriend...
Of course not.
Her fingers tapped rapidly against her folded arms, and a faint twitch ran across the brow of her elegant face.
She looked to be in an extremely bad mood.
"Hey, Amamiya, don't keep your girlfriend waiting too long."
"Shut up."
Shirou rose from his seat.
You guys had better watch yourselves when you walk home at night.
Especially for any Gandr that might suddenly come flying out of the darkness. Miss Tohsaka could hold one hell of a grudge...
Shirou made his way past his jeering classmates and stopped in front of her.
Rin Tohsaka said nothing. She simply turned around and walked off, with Shirou quickly following behind.
The two reached the deserted end of the hallway.
"What's wrong, Tohsaka... need to borrow some money?" Shirou asked, trying to lighten the mood.
"Don't play dumb. You noticed it too, didn't you? Someone's setting up a Barrier inside the school."
Rin Tohsaka narrowed her eyes.
Shirou seemed unconcerned. "It's so blatant that even a complete amateur should've noticed something was wrong."
Rin Tohsaka agreed. "An amateur, huh... True. A Barrier that makes its presence this obvious can only be called third-rate."
"If you're going to set one up, keeping it hidden until it's complete is what separates the first-rate from everyone else..."
"More importantly, setting up something this disgusting on my turf? Whoever did it must have a death wish."
That was the real reason Rin Tohsaka was angry.
Doing something like this at the school she attended was practically a declaration of war against her.
As one of the administrators of Fuyuki City, the Tohsaka Family had a responsibility to oversee Magecraft activity within the territory.
And Homurahara Academy was part of Rin Tohsaka's everyday sphere of activity. For someone to set up a Barrier here without notifying her beforehand was an unmistakable provocation.
Worse, the Barrier's nature was still unclear. If it harmed any ordinary students, the responsibility would ultimately fall on her.
"Whether they're third-rate or first-rate, whoever did this needs to be taught a lesson. You agree, don't you, Shirou?"
"Why are you dragging me into it?"
Shirou's answer left Rin Tohsaka stunned.
"Huh...? Shirou, aren't you angry?"
"It doesn't feel like a harmful Barrier," Shirou said.
Rin replied, "Putting aside that completely baseless intuition of yours, involving ordinary people in Magecraft is already a violation of the fundamental principle that Magecraft must remain hidden."
Shirou said, "I'm not a Clock Tower Magus, so I don't really care about that principle..."
Rin gave him a suspicious look. "Amamiya, you didn't set up this Barrier yourself, did you?"
Shirou answered as though it were obvious. "If I'd set it up, I wouldn't have left traces this obvious."
"That's true. Amamiya, your Barrier techniques are surprisingly sophisticated..."
"Actually, you've even mastered the 'Reality Marble,' something modern Magi supposedly can't master at all."
A shadow fell across Rin Tohsaka's face.
For roughly eight years now, she had treated Shirou's back as the goal she needed to catch up to.
And yet, despite being widely acknowledged as a genius herself, the gap between them was large enough to leave her in despair.
After all these years, Rin Tohsaka had not only failed to close the distance between herself and Shirou, she felt as though it was growing wider and wider.
At this rate, catching up to that back would remain nothing more than an impossible dream... Sigh.
"......Fine. I won't ask you. I'll deal with this incident myself."
Rin Tohsaka tossed her beautiful black hair and gave a huff.
"Is it really okay to leave Rin alone?"
Tiamat released her Spirit Form and appeared beside the boy, asking anxiously.
Shirou said nothing. He simply watched Rin return to her classroom.
...
Rin Tohsaka was fired up.
As a Magus, she could hardly tolerate someone walking all over her.
It had been a long time since she had faced an actual enemy.
And she would never be satisfied unless she properly repaid the rude bastard who had the nerve to set up a Barrier in someone else's backyard.
During lunch break, Rin Tohsaka was planning what she would do that evening as she returned from the cafeteria to her classroom.
That was when she noticed a middle school girl slowly making her way down the hallway, her steps unsteady.
The girl appeared to be carrying a stack of handouts, and just looking at her made Rin nervous.
"Let me help you, Sakura."
"Ah, um... thank you, Tohsaka-senpai."
Sakura Matou gave a small start when she saw who had spoken to her.
"What are these, English handouts? Wait, first-year high school English? Aren't these Fujimura-sensei's?"
"How did she even come up with the idea of making a middle school girl carry her handouts?" Rin Tohsaka asked, utterly speechless.
"Um... Fujimura-sensei said... 'Be proud, Sakura! Being allowed to run errands for me is the greatest honor you could ever receive!'"
"'I can't count on that kid Shirou anymore. You're actually the one I've always had the highest hopes for.'"
"'Once you enter high school, Sakura, you'll have to lend me a hand so I can reclaim the Kyudo Club, okay?'"
Taiga Fujimura had recognized Sakura Matou's potential for growth in areas other than her chest.
She might still be an introverted middle school girl now, but one day she would grow into an indispensable figure in the Kyudo Club.
That was why Taiga Fujimura had chosen to "look after her" by making Sakura run errands, all in an effort to recruit a promising future underling.
"What kind of Showa-era yakuza mentality is that? Seriously..."
Rin Tohsaka sighed. "Here, give me half."
"Ah, yes. Thank you, senpai," Sakura Matou said somewhat stiffly.
"It's fine, it's fine."
The two sisters, interacting as senior and junior as they always had, headed toward the faculty offices.
"Sakura, are you feeling better?"
"Huh?"
Sakura Matou froze for a moment, then quickly realized Rin was talking about her absence from school yesterday.
"I-I'm much better now."
"I see. If you still feel unwell anywhere, just tell me. I have some secret medicine passed down through the Tohsaka Family... Ahem. I mean, I have some very effective medicine."
"Okay."
Sakura Matou felt guilty for lying and couldn't bring herself to meet her sister's eyes.
Rin Tohsaka, meanwhile, was completely absorbed in this ordinary exchange with her younger sister and failed to notice anything unusual.
"...Um, this is far enough, senpai. All I have to do now is take these to Fujimura-sensei."
"Really? Then I'll see you later."
"Oh, and if Fujimura-sensei does anything weird, tell me. That woman has no sense of limits. Staying quiet will only make things worse."
Rin Tohsaka handed the remaining materials back to Sakura.
She had intended to return directly to her classroom, but after taking a few steps, she stopped.
"Sakura, how have things been lately?"
"Ah... yes. Everything's fine. I'm very happy right now."
Sakura Matou smiled as she said it.
Seeing that smile only strengthened Rin Tohsaka's resolve to protect this peaceful everyday life.
...
The day came to an end.
The classrooms gradually emptied, and the school building slowly sank into darkness.
Sunset was approaching.
Once the crimson sun disappeared beneath the horizon and night fell, there would probably be no one left at school.
Rin Tohsaka began her duties as the head of the Tohsaka Family.
First came a preliminary investigation of the Barrier.
Once she understood what kind of Barrier it was, she could decide whether to destroy it or leave it alone.
The investigation did not take much effort, and she soon reached a conclusion.
The Barrier currently established over Homurahara was not particularly dangerous in itself.
It was neither a Barrier designed to drain human vitality nor the sort of exclusion Barrier most commonly found in the world of Magecraft.
It was some kind of detection Barrier.
A Barrier that collected the biometric data of everyone who entered the school.
If one ignored the complete violation of privacy, it could just barely be considered harmless.
It was like an underwear thief who only took measurements without actually stealing anything. Revolting all the same.
Rin Tohsaka's anger only grew as she began searching for the Barrier's anchor points.
After examining the school one location at a time, she eventually reached the rooftop.
Outside, night had completely fallen.
The school's six o'clock curfew had long since passed. It was already eight.
Rin Tohsaka was the only person left at school.
"...Is this the seventh one? It looks like this is the starting point."
Seven strokes of a seal had been brazenly drawn across the rooftop floor.
The reddish-purple markings were visible only to Magi. Their form was unlike anything she had seen before, and even the material used to inscribe them was something she had never heard of.
"Tsk... I can't erase this by hand."
Rin Tohsaka began to sense that something was wrong.
Because the Barrier itself had been constructed so crudely, she had naturally assumed its creator was some half-baked outsider Magus.
They had probably chosen Homurahara because they had heard that the head of the Tohsaka Family attended school here.
But judging from what she had found, Rin Tohsaka realized she might have underestimated her opponent.
The technique used to construct the Barrier was clumsy, but the Mystery of the Magecraft itself was exceptionally high.
Rin Tohsaka could temporarily erase the Mana within the seal, but she could not destroy the seal itself. The moment its caster sent Mana through it again, the Barrier would probably return.
Still, Rin Tohsaka was not someone who gave up easily.
Eight years ago, when her father had suffered a complete defeat, the young girl had already sworn something to herself.
Someday, I'll catch up to that guy.
The girl approached the seal on the ground and extended her left hand, where the Tohsaka Family's inherited Magic Crest had already manifested.
"Abzug Bedienung Mittelstnda... (Erasure and Extraction Ritual, Section Two)."
Rin Tohsaka poured Mana into it all at once, and the seal on the ground disappeared.
The result was even better than she had expected.
Was it because she had incorporated the Reinforcement Magecraft technique Shirou had taught her before? Even the effectiveness of the spell formula had improved.
Rin Tohsaka felt a little pleased. Apparently, all her secret practice had paid off.
Granted, she had still borrowed that guy's knowledge in the end, but at least she had managed to erase the troublesome seal.
"!!!"
Without warning, a terrible chill swept through Rin Tohsaka's body.
The girl whirled around.
Atop the water tower stood a purple apparition that seemed to melt into the night.
Alluring purple hair drifted in the evening breeze. Her slender limbs curved into a voluptuous figure, while her beautiful features were almost dreamlike.
The tall woman stood some ten meters above Rin Tohsaka, looking down at her.
Her jewel-like eyes gleamed as they fixed Rin with a piercing stare.
It felt like being a rodent caught beneath a snake's gaze.
...I can't move?
By the time Rin Tohsaka realized what was happening, she found herself unable to move even a single step.
"...You're the one who set up this Barrier, aren't you?"
"Trying to buy time with conversation while you break the spell...? Give up. These eyes are not something you can free yourself from."
The woman spoke casually, then leapt from the water tower.
Her landing was graceful, yet made not the slightest sound.
Just like a snake.
"Who... are you?" Rin Tohsaka asked in a low voice.
This had nothing to do with Magecraft. Pure fear had frozen her spine.
The demonic presence radiating from the woman before her reminded Rin Tohsaka of the Dead Apostle Ancestor she had once confronted.
"That is what I should be asking... Who are you?"
The woman stood half a head taller than Rin Tohsaka. Looking down at her, she reached out and took the girl by the chin.
"Magus, are you my Master?"
"Master...? You're a Servant!?"
Rin Tohsaka's heart jolted in surprise.
Why was a Servant at the school?
Had the Holy Grail War begun?
No. There was already the precedent of Tiamat, who had manifested independently of the Holy Grail War.
Then was this woman looking for someone?
The woman, Rider, Medusa, studied Rin's reaction before quietly shaking her head.
"It appears you are not my Master after all..."
A trace of disappointment passed through Medusa's eyes.
She had been somewhat pleased when her detection Barrier picked up a Magus, but judging by Rin Tohsaka's reaction, this clearly was not the person she had been searching for.
"You're no use to me anymore."
"No use?"
Rin Tohsaka's lips curled into a cold smile. "Planning to kill me?"
"Kill you?"
Medusa frowned slightly, unable to understand why Rin Tohsaka had reached that conclusion.
Medusa raised one hand, preparing to make Rin Tohsaka forget everything she had seen that night.
At that moment, another voice rang out.
"Wait! No! Don't hurt her, Rider!!"
The third person's voice broke into the confrontation.
The chill enveloping Rin Tohsaka's entire body vanished at once.
"...Sakura?"
"...Don't come any closer! It's dangerous, Sakura!"
Medusa and Rin Tohsaka reacted at the same time. Rin shouted desperately at her younger sister as Sakura ran toward them.
No matter what happened, she could never allow Sakura to become caught up in danger. That was Rin Tohsaka's most unwavering conviction.
She forced herself to break free from the binding effect of the Mystic Eye.
Medusa had not actually released the true "Petrifying Mystic Eye." She had merely used her gaze to restrain Rin, which gave Rin Tohsaka the opening she needed to break free.
Rin Tohsaka pulled out the gem she had kept on hand for emergencies.
Sensing unmistakable hostility, Rider instinctively tightened her grip around the chained sword that materialized from empty space.
"Tsk!"
Rin Tohsaka fired the gem at point-blank range.
Even against a Servant, it should still inflict some damage.
"..."
Medusa's chain shot toward the girl's wrist.
No matter how thoroughly a modern Magus Reinforced their body or constructed defenses, none of it would matter against her attack.
"......"
It all happened in an instant.
Like a whirlwind, someone flashed between the two in the very moment their deadly clash began.
The gem Rin Tohsaka had fired was knocked aside and burst into fireworks in midair.
Medusa's descending Short Blade was firmly blocked before it could pierce the girl.
Standing between them was a red-haired boy.
"Amamiya...?"
"S-Senpai...?"
Rin Tohsaka and Sakura Matou spoke at almost the same moment.
For that single instant, time seemed to stretch into eternity.
Moonlight traced his slender silhouette, while his distinctive red hair swayed in the turbulence of surging Mana.
Even in the darkness, those twilight-colored eyes shone brilliantly.
They both knew perfectly well that this was hardly the time for it.
Even so, the sight of that refined young man beneath the starry sky left both sisters staring at him without realizing it.
The scene before them tonight was something they would probably never forget for the rest of their lives.
"Senpai... Tohsaka-senpai!"
Sakura Matou ran breathlessly over to Shirou and Rin.
The girl planted both hands on her knees, her chest, far beyond what one would expect from a middle schooler, rising and falling dramatically.
"Um... this is actually a misunderstanding. Rider-san isn't..."
As Sakura Matou tried to explain, she looked up at Medusa.
Only to find Medusa staring fixedly at Shirou's face.
"Uh..."
Sakura Matou's heart skipped a beat.
A sudden sense of foreboding rose within her.
A woman's intuition.