001 - What Makes it Hard to Go Home ?

"Did we really need to be on top of this building?" Sakura asked, glancing nervously over the edge.

"What do you mean? This is the best place to watch over the entire town," Rin replied, her gaze fixed on the city below.

"I mean... nevermind." Sakura sighed, realizing there was no point in arguing.

They were currently on the tallest building in Fuyuki City, scouting for any unusual activity. They were also waiting for Saber and Emiya to join them later.

"It's pretty cold up here," Sakura muttered, rubbing her hands together in a futile attempt to warm herself.

"Hmm? Oh, right, I still haven't given you my spell, have I? Come here, Sakura."

Sakura stepped closer to Rei, and with a simple gesture, he touched her, surrounding her body with a gentle magic spell, instantly warming her against the cold.

Rin, watching Rei casually use his magic, asked, "How can you use magic so easily? Even though you explained it to me, I just can't get it to work."

"I don't know, maybe it's the difference in the structure of your body compared to those from my world. Your body is too limited, so neither of you can use magic like we do back there," Rei replied calmly.

"Hahhh... There goes my dream of actually casting magic," Rin sighed in disappointment.

"It's fine, onee-chan. Don't be sad—here, eat this," Sakura said, and suddenly, her shadow moved, floating in front of them.

From the darkness of her shadow, it opened, revealing a snack that Sakura had stored. "I brought this in case you got hungry, onee-chan."

Rin gave Sakura a blank stare. Despite Sakura possessing the powerful Imaginary Numbers ability, she often used it for mundane things like storing snacks or throwing away trash.

Resigned, Rin said, "Thank you, Sakura," as she accepted the snack and began eating it.

"You know, you're going to get fat if you keep eating like that, Rin," Rei suddenly teased.

"Wha!? I'm not fat! And it's fine! I rarely eat snacks like this!"

"But you always eat something in the middle of the night, don't you?" Sakura chimed in.

"You know!?" Rin gasped, clearly shocked that Sakura was aware of her late-night snacking habit.

Sakura and Rei laughed at Rin's reaction, watching as she pouted and ate her snack in frustration.

"I'm sorry, onee-chan, but you're just so easy to tease," Sakura said, giggling.

"Yeah, you're just cute when you get teased like that," Rei added, amused.

"Hmph, I don't care if you call me cute! You think that's enough to make me stop being mad!?" Rin snapped back, but her words didn't match her expression, as both of them could see her cheeks turning slightly red.

"Come on, Rin, don't be like that~," Rei approached her from behind, placing his hands on her shoulders in an attempt to comfort her.

"Hmm!" Rin turned her head away, refusing to look at him.

Rei kept teasing her by poking at her slightly puffed cheeks, before saying, "There's another kind of magic I can teach you, you know~."

He noticed Rin's ears twitch as if she was interested in what he said. "In my world, there are many types of magic, so we just need to find one that's compatible with your bodies."

"Like…what?" Rin asked quietly, her curiosity now evident.

Rei smiled and released her shoulders, taking a few steps back.

"Like this," he said, moving his right hand forward and using two fingers to trace something in the air.

"!!" Sakura gasped in surprise as she recognized the thing that Rei's write.

"Spellweaving: Mana Burst," Rei said as the rune he traced in the air glowed brightly before moving toward Rin, entering her body.

"!?" Rin, who had been looking away, suddenly felt an overwhelming surge of power fill her, catching her completely off guard.

"What just happened!?" she exclaimed, standing up quickly—too quickly. The sudden burst of strength caused her to jump high into the sky, far higher than she intended.

"WHAT!! REIIIII!!!" she screamed as she realized she was now falling rapidly back toward the ground.

"Onee-chan!!!" Sakura panicked, watching her sister plummeting from the sky.

Rei, however, calmly jumped up and caught Rin mid-air before she could hit the ground and destroy the building beneath them. Given the immense power surging through her, the fall wouldn't have harmed Rin, but the impact would have obliterated their surroundings.

Landing smoothly beside Sakura with Rin in his arms, Rei smiled and asked, "How is it? Does it feel good?"

"..." Rin was silent, still processing the overwhelming sensation coursing through her body, her face a mix of shock and awe.

"Is that a Primordial Rune?? You know how to use those too?" Sakura asked Rei, eyes wide with curiosity.

"No, this is an Elemental Rune. It has the ability to manipulate different elements and strengthen someone, like I just did with Rin," Rei explained, lowering Rin carefully to the ground. "You can also boost your magic with it, but since I rarely use magic myself, I don't usually need to."

Rei added, "Right now, your body is overflowing with power, Rin, so be careful. If you fought the previous Saber like this, you'd probably give her a good fight."

Rin was still silent, examining her body with a stunned expression, which made Sakura worry. "Onee-chan, are you feeling okay?" she asked, concerned.

Then, Rin finally spoke, excitement building in her voice. "This is..."

"This is AMAZING!" she exclaimed, her face lighting up. "I've never felt anything like this before! My body feels so light!!!"

Rin started moving around, throwing punches into the air. Each punch created gusts of wind that blew forward with tremendous force.

After some time, Saber and Shirou finally appeared at the top of the building.

"What's going on?" Shirou asked the three, noticing that Rei was carrying Rin in his arms.

"She's just a bit too high on power right now, don't worry about it," Rei replied casually.

"I see..."

But Saber, sensing something different about Rin, decided to ask, "Did you give her your Mana as well? Her presence feels much stronger than before."

"Giving her Mana too?" Sakura echoed, glancing at Saber.

"Nope, I didn't do that. I just enhanced her with my Rune. But anyway, that's not important. Let's start the patrol," Rei said as he suddenly picked up Sakura and leaped off the building.

"What's going on? He's acting strange," Shirou muttered, confused by Rei's sudden actions.

"I'm not sure," Saber responded thoughtfully. "But we should follow them, Master." She led Shirou as they jumped from the building to catch up with the trio.

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They spent several hours, until late at night, patrolling the city, erasing Caster's magic circles from different buildings. Some of these magic circles had traps, summoning skeleton monsters to attack them. However, they easily defeated all the creatures and continued their mission.

Eventually, they decided to take a break in a nearby park.

"Is that all of them?" Shirou asked Rei and Saber, as they were the ones who could easily sense where the magic circles were hidden.

"Yes, that should be all of them," Rei replied.

"But there were so many... Why does she need so many magic circles?" Saber muttered.

"Because your teacher isn't a mage, so he can't provide the Mana Caster needs to remain in this world and use her abilities," Rei answered, glancing off into another direction.

"Hmm, so when are we going to confront teacher Kuzuki? We can't just let him and Caster continue absorbing people's life force," Shirou asked the group.

"We need a plan for that," Rin replied, munching on another snack. "Like Rei said, Caster probably enchanted Kuzuki and placed traps on his body. We can't just approach them carelessly."

For some reason, since Rei had enhanced her body with his power, Rin had been constantly hungry, and Sakura had been handing her food non-stop.

"Can't we get the same buff that Rei gave you?" Shirou suggested.

"I don't know, you can ask Rei about that. I only found out he could do that a few hours ago."

"Rei?" Sakura called out, noticing that Rei was staring intently in a certain direction.

"This feeling... Something's happening," Rei murmured, and before anyone could react, he vanished from the spot.

"Wha!? He's gone??" Rin exclaimed, looking around to find him.

"Saber, can you sense him?" Shirou asked his Servant.

"Yes, I can still sense him, but he's moving farther away. We need to go after him," Saber said urgently.

"Alright then. Sakura and I will go together. I can still feel the power from Rei. You and Emiya stick together," Rin instructed.

Meanwhile, Rei, who had arrived at the place where he sensed something was off, found himself in a narrow alleyway drenched in blood.

"You..." he muttered, his sky blue eyes scanning the grisly scene before him.

The alley was painted in crimson—blood splattered across the walls and pooled on the ground, yet, strangely, no human remains could be seen. Not a single body or even a fragment was left behind, only the unmistakable aftermath of violence. Despite the darkness, Rei could see it all clearly. The eerie silence amplified the unsettling atmosphere.

Standing in the middle of this gruesome scene was a woman with long, flowing purple hair. She stood unmoved, her back turned to Rei, seemingly unaffected by the carnage surrounding her.

As Rei stood there, examining the eerie scene, he suddenly heard the woman giggle—a creepy, unsettling sound that echoed through the blood-soaked alleyway. It was a soft giggle at first, but it slowly escalated into something more sinister, sending a chill through the air.

The woman with the long purple hair slowly turned around to face him. Her wide smile stretched unnaturally across her face, eyes gleaming with a terrifying madness. The expression was unsettling—almost inhuman, a grotesque contrast to the quiet moment before.

Rei's gaze sharpened when something dark began to seep from beneath her. It was an ominous, black substance with faint hints of red, crawling and writhing as it spread across the ground like living shadows.

In an instant, the dark tendrils shot toward Rei with terrifying speed, aiming to ensnare him. They moved like serpents, twisting through the air, leaving behind a faint, menacing glow.

Rei stood perfectly still as the dark tendrils closed in. Yet, as they neared his body, they halted, frozen mid-air as if unable to touch him. Within moments, they began to dissolve, slowly evaporating into the night air as if their very existence was being erased.

He didn't even flinch, merely watching the woman in front of him with a calm intensity.

Not long after Rin, Shirou, Sakura, and Saber arrived at the scene. Rin gasped, her eyes widening in shock as she took in the bloodied alley.

"What the!? What happened??" Rin shouted, her voice trembling slightly as she turned toward Rei.

Sakura's face paled, her hands covering her mouth in disbelief. Shirou, too, was wide-eyed, his gaze locked onto the purple-haired woman standing amidst the carnage.

"No way!" Shirou muttered, recognizing the figure before them.

Saber immediately unsheathed her Excalibur, her instincts screaming danger. She stepped in front of Shirou, placing herself between him and the woman. "Master, this is dangerous. Stand behind me," she said, her voice firm as she pointed the darkened holy sword at the mysterious figure.

"No, Saber, wait! I know her!" Shirou quickly interjected, his eyes still fixed on the woman. His tone carried both surprise and concern. The situation felt surreal, but he couldn't shake the familiarity of the woman standing in the midst of all that blood.

"No, Master! This woman is dangerous! We need to get rid of her right now!!" Saber shouted, her voice firm and resolute as she dashed forward with blinding speed, her Excalibur raised to strike.

"Wait, Saber!" Rin and Sakura yelled in unison, both feeling the overwhelming sense of danger radiating from the purple-haired woman. They knew this was no ordinary opponent, and Saber's bold approach might lead to disaster.

Yet the woman remained still, her unnerving smile widening, as if relishing the attack. Even as Saber closed in, there was no movement from her, no effort to evade. But just as Saber was about to strike, her instincts screamed at her, and she stopped her advance, swiftly deflecting several beams of energy that had appeared out of nowhere.

While Saber's attention was momentarily diverted, the woman seized the opportunity, launching her dark tendrils toward her with terrifying speed. The air seemed to thicken with malice as the tendrils twisted through the air.

"Spellweaving: Quadruple Hex." Rei's calm voice cut through the chaos as he swiftly conjured a Rune. Four rays of light shot forth, each one glowing with a different color, representing the elements of fire, water, wind, and earth. The beams collided with the tendrils mid-air, tearing them apart and dissolving them into nothingness.

The clash of energy lit up the dark alley, and for a moment, the battle seemed to come to a standstill. Saber's eyes darted between the woman and Rei, realizing just how precarious the situation had become. The woman, however, remained unfazed, her unsettling grin still stretched across her face, as if none of this mattered to her.

"Come here, Saber," Rei commanded, his voice calm yet firm.

Without hesitation, Saber's body moved on its own, retreating to Rei's side. "Huh?" Saber glanced at him in confusion, her body suddenly move without her realization.

Rei's eyes remained locked on the purple-haired woman in front of them. "Your Servant... If Gilgamesh were here, I'm sure he'd be laughing really hard right now," Rei said with a smirk, knowing full well how Gilgamesh would mock such a scenario.

Suddenly, something heavy landed beside the purple-haired woman. The air grew thick as another figure began to materialize. As the form solidified, they saw another woman—one whose lower half was that of a snake, her upper body human. Her long purple hair flowed down her back, but at its ends were multiple snakes, hissing and coiling restlessly.

The serpentine woman eyed Rei and the others with an unsettling smile, her slitted eyes filled with malice. Her very presence exuded danger.

"Gorgon…" Rei muttered.