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A Tale of Twintails: Spear IF

Summary:

A what if involving the fusion of two Subaru's variant. Tailblack and Spearbaru!

Notes:

I would like to thank EternalWhisper and Cardinal for permitting me to write this.

DISCLAIMER: I don’t own Re: Zero, it belongs to Tappei Nagatsuki.
And this variant belongs to EternalWhisper and Cardinal.

(See the end of the work for more notes.)

Chapter 1: The Four Who Weren’t Meant to Come

Chapter Text

The sun had set about twenty minutes ago. The sky was a deep blue fading into black, and the streetlights flickered on one by one, casting orange pools across the sidewalk. A few cars passed. A couple of people walked their dogs. 

The convenience store stood out against the dim street, bright and steady. Its automatic doors slid open and shut every few minutes, letting out brief bursts of cool air and the soft beep of the register.

Inside, Natsuki Subaru stood near the back.

He flipped through the latest volume of Shonen Jump, holding it open with one hand while the other stayed tucked in his jacket pocket. He’d been gaming all day. He was tired, but the new chapter had dropped, so here he was.

He turned a page. The paper crinkled softly. A confession scene. The protagonist, red-faced, poured his heart out to the female lead.

"Classic," he muttered to himself.

He flipped again. Then his vision shifted.

At first, it was nothing, just a faint pressure behind his eyes, like the start of a headache. He blinked and rubbed at them.

“Ugh… figures.”

He looked back down at the page. The words blurred. Black ink bled into the white paper, then pulled back again. He squinted, trying to focus.

Something wasn’t right. The edges of his vision tinted… purple. No, red...or both.

Purple smoke curling from the left. Red fire flickering from the right. They crept inward, slow and steady, meeting somewhere behind his eyes.

"What the…?"

His balance slipped. He took a step sideways to steady himself and slammed into a display of potato chips. The rack rattled. The magazine slipped from his fingers and fluttered to the floor. He didn't notice as his shoulder clipped more displays, knocking them over. They wobbled, teetered, then crashed. Bags scattered across the linoleum in a rainbow of crinkly plastic.

"Hey!" the clerk shouted from the register. "What are you doing?!"

"I—I don't..." Subaru's voice came out slurred.

His legs wouldn't cooperate. One step forward became two steps sideways. He grabbed a shelf for support. The metal groaned under his weight, and a row of instant ramen cups avalanched onto his head.

BAM. BAM. BAM.

Three cups bounced off his head before dropping on the floor.

"I'm sorry! I'm sorry!" Subaru gasped, but he couldn't stop moving. Every muscle pulled in a different direction, like tangled strings yanking him apart.

The colors bled deeper into his vision now. Purple and red twisted together, warping everything they touched. The store smeared and stretched, like paint running under water.

His arm knocked into a rack of magazines. Pages burst into the air, idols, cars, bright recipes, fluttering around him.

He stumbled into a freezer door. It swung open, blasting cold air across his sweating face.

Then he tripped over his own feet.

His chin hit the floor. His teeth clacked together. The pain was sharp and real, but already fading beneath the growing pressure behind his eyes.

"What's...happening...?"

He tried to push himself up. His arms gave out.

He collapsed onto his side. His cheek pressed against a cold tile floor strewn with debris. His eyelids were heavy, so heavy, like someone had tied weights to each lash.

"Mom…"

The thought came without permission.

"Dad…"

Before he lost consciousness, a third color resembling orange briefly appeared in his vision, followed by a click sound coming from his wrist. 

───▽───

When Subaru opened his eyes, the fluorescent lights were gone. Once his eyes had fully adjusted, everything had changed. Long hair spilled across his face, black with orange tips, briefly crossing his view. He reached up and touched it, confused. His fingers ran through the strands, then gathered them. Two distinct tails. He pulled one forward and stared at it.

"Twintails...?"  

His eyes moved around, looking at his surroundings. The buildings looked like something out of Europe, packed close together with signs he couldn’t read. The writing was strange, nothing he recognized. The people were just as strange, some had animal ears, tails, and even fur. Faces that didn’t exist anywhere on Earth. 

A carriage rolled past on heavy wheels, pulled by something his brain couldn’t understand. He gave up and just called it “fantasy.” He stared at everything so hard it felt like he could burn the scene into his mind out of pure disbelief. Then, a burst of excitement surged up through his chest, his old wish, the silly fantasy he had dreamt about, had finally come true. 

"Have I really been...isekaied to another world?!" he blurted out loudly. His voice climbed even higher on the last word, as he barely kept himself from laughing with pure joy. 

Except the voice that came out of his throat wasn't his. 

It was softer, angelic, it was like honey to the ear. Like a melody you wouldn't want to stop. But it was so wrong at the same time, so wrong that the excitement he had felt disappeared. He tried again immediately, hoping that repetition could bully his throat into behaving. 

"W-What..?"

But the same voice that came out was still soft, smooth, and not his. His stomach dropped. Panic hit in a brutal rush. His body reacted before his mind could catch up, and he looked down. 

And that's when he realized he was lying on top of a pile of bodies. Three of them, stacked together like a pyramid. 

At the very bottom, flat on his stomach with his face pressed sideways against the stone, was a young man in dark clothes. In his hand rested a sleek and elegant-looking sword with a blue gem in the center of the hilt.

On top of him, sprawled across the dark-haired one's back, lay a blond guy dressed in a neat green outfit, resembling a school uniform. Like the first guy, he held a sleek, stylized bow. The bow was mostly white with elegant curves, accented by gold details at the ends, alongside a yellow gem that was set near the lower section of the bow, right above the grip area where his hand was holding it.

And on top of the bow guy, resting across his back and shoulders, was a slightly older guy in a green tracksuit with a shield strapped to his right arm.

Lastly, there was Subaru, lying on top of all three like the peak of a human pyramid.

"W-Who are these people?"

He raised his hand and, to his surprise, found a spear in his grip, a slender, double-ended spear with a smooth, pale shaft and gold accents. It features a narrow blade at the top with a glowing red gem near its base and a sharp spike at the bottom.

His eyes lingered on the spear for a bit before it shifted toward his own hand. It wasn't the manly hand he expected. Instead, what greeted him was a small, delicate hand with slender fingers, partly hidden by fingerless gloves that extended up his forearms.

"H-Huh..? What the...?!" Subaru was interrupted before he could finish voicing his confusion. 

A low groan rose from beneath him, then another, and a third, deeper and more strained than the rest.

Subaru’s small, gloved hands pressed harder into the back of the green tracksuit as the body beneath him twitched.

The shield-bearer stirred first. His shoulders tensed, and his head lifted slightly off the ground.

“Nngh… what the hell…?” His voice came out rough, thick with a lingering daze.

Beneath him, the blond with the bow let out a soft, airy sound, half yawn, half complaint. His fingers twitched around the grip, and his legs shifted, giving a weak, uncoordinated kick against the man pinned at the bottom.

“Mm… five more minutes…” he mumbled, still too out of it to realize he was lying on someone.

At the very bottom, crushed against the cold stone, the dark-haired swordsman exhaled sharply. His face remained turned to the side, cheek pressed flat, but his free hand scraped weakly against the floor, fingers curling with effort.

“…Too heavy,” he rasped, voice tight with strain. “Get… off…”

For a second, nothing changed, but then the hand scraping against the stone stopped.

The sword guy's fingers dug into the ground, trembling...then tightening with sudden strength. 

His eyes snapped open.

"What?" The word came out low, confused, then immediately sharpened into irritation.

His body tensed uncontrollably. And then, he pushed. Not a weak shove nor a tired nudge, but a full, sudden burst of force.

“OFF!!!”

The entire pile exploded apart. Subaru yelped as the “ground” beneath him vanished. The shield guy was launched backward while the bow guy rolled off to the side, and Subaru himself was thrown upward just enough to completely lose balance.

CRASH.

All four bodies hit the stone in a messy, painful chorus.

“GAH!”

“HUH?! What the hell?!”

“Ah..!!”

“Tch!!”

The impact echoed across the street. Subaru landed hard on his side, breath should have been knocked clean out of his lungs, and pain should have flared through his shoulder, yet he felt nothing as he rolled once, twice, before finally stopping on his back, staring up at the sky. 

“Ow…ow…ow…”

A few feet away, the blond archer groaned, clutching his head. 

“What was that for?!” he snapped, his voice no longer sleepy, but sharp and annoyed. 

The shield guy pushed himself up onto one knee, rubbing the back of his neck. 

“W-Where am I?” he said as he looked around.

---

3rd POV

The swordsman was already standing.

He brushed dust off his dark clothes, his grip loose on the sword at his side, but his eyes were anything but relaxed. They moved quickly, scanning everything with sharp focus.

“What kind of place is this…?”

His gaze dropped to the sword in his hand. His eyes instantly widened as recognition hit him: the weapon from Brave Star Online. 

“…No way…”

He lifted the weapon slightly, turning it just enough to catch the light. The shape, the balance, the detailing, there was no mistake.

“…It’s from Brave Star Online…” he muttered. 

Every line, every curve, every tiny detail, matched perfectly. His fingers tightened around the grip. He had held this sword before. Not once. Not twice, but hundreds…thousands of times. Late nights, endless grinding. Fights he barely won and ones he dominated. The weight of it had become second nature to him. 

“…How did I end up here…?”

His thoughts turned inward, searching, reaching for the last thing he could remember, and then it hit.

“I died.”

The thought surfaced, the memory of him shoving his friend aside and then being stabbed by a knife. He unconsciously rubbed his side as he recounted the story. He didn’t fully remember what happened next. Only blood…so much blood…and the feeling of fear…of not wanting to die…the cold…dying was so cold…

He pushed it down. Don’t need to think about that now. Don’t need to think about it ever. 

───▽───

Subaru pushed himself up, his arms trembling, not from weakness, but from how wrong they felt.

They were too thin. Too smooth. Wrapped in a sleek black fabric that clung to his skin like it had been painted on. He looked down. His hands. No, not his hands. They should have been those of a teenage boy, but instead they were small, delicate, almost fragile. He stared at them.

“Th-these can’t be my hands…”  Subaru thought.

Slowly, he raised one hand to his chest. 

The material there was different. Sleeveless, tight around a high collar that pressed lightly against his throat. His fingers brushed the center of his chest and stopped against something solid. A gold star-shaped emblem, set into the suit.  Below it… skin. His breath caught.

His stomach was exposed. The suit ended just beneath his ribs, leaving his midriff completely bare. He jerked his hand away as if he’d been burned. 

“No,” he whispered.

Maybe it was a dream. It had to be. But his voice came out high. Soft. Wrong.

“No… no, no…!”

He looked down.

Tight black leggings clung to his legs. Plates of armor were strapped to his thighs and knees. His boots were heavy, edged in sharp, clean shapes, lined with faint orange light.

“This isn’t my body!” 

His hand slid down his side.

Thin lines ran along the suit, glowing orange. They pulsed softly, like something breathing under the surface. His fingers brushed against something at his hips. Round. Solid. He grabbed them, two circular cores, warm in his hands.

“What am I wearing…?”

Panic rose in his chest. He tried to tear it off. Searching for a zipper! A seam! Anything! There was nothing. The suit had no opening. It clung to him like a second skin. Like it was his skin. It felt wrong. Like some twisted version of a magical girl outfit. 

He reached behind his back, searching for an edge, anything he could grab. His hand brushed against something else.

He froze.

It felt like wings. Not flesh. Not metal. Something in between. They curved out from behind his hips, shaped like flames. Firm, yet slightly flexible. He could see them in his peripheral vision and, worse, feel them, as if they were part of him. 

"I'm a...a magical girl...?" The words came out weak. They tasted like ash.

A shadow fell over him, interrupting his thoughts. Subaru looked up. 

The shield guy stood there; his tracksuit was dusty, and his face showed both confusion and concern. A moment ago, he had been watching his surroundings, then his eyes locked onto Subaru, who was still rubbing hi-her head.

He hunched over and offered Subaru his hand. 

"Hey," his voice was shaky, maybe embarrassed, sweat appeared on his temple as he stretched his hand towards the beautiful girl. "You alright?" 

Subaru stared at the outstretched hand, then at the now blushing boy. He forced his lips into a smile.

“Yeah,” he said. The voice still didn’t feel like his. Nor his body. “I’m fine.”

He took the hand.

The shield guy pulled him up with a short grunt. Subaru’s boots clicked softly against the stone as he found his footing, but even standing straight, his head barely reached the man’s chest. He had to tilt his chin up to meet his eyes. 

Another thing that felt wrong.

“You don’t look fine,” The shield guy spoke, looking around with a sweat at his temple. His voice was low and steady, even though surely he was more confused than Subaru, it was evident from his widened eyes.

Subaru let go of his hand hi-her face red as tomato,  turning away “I just… hit my head,” he blurted out, brushing dust off hi-her outfit. The faint orange lines along the fabric felt heavenly under his fingers, catching hi-her attention for a second, when he spoke hi-her voice was smothered with awe, eyes widening. “...When we fell...That’s all...”

The shield guy didn’t look convinced, but he didn’t press.

A short distance away, the sword-and-bow guys had already regrouped. They stood close, voices low, trading observations as their eyes moved across the unfamiliar street, alert, cautious, already trying to make sense of it all.

And yet, beneath that focus, there was something else. Subaru rubbed his neck and he could see a faint excitement, barely restrained flickering in their eyes. 

"Hey! Are you guys from Japan, too?" Subaru called out.

They turned at once, surprise flashing across their faces as their eyes landed on him...no, on the girl in the strange, questionable eye-catching outfit. 

The sword guy frowned, looking him up and down. "What in the world are you wearing?"

While the bow guy blinked, a bead of sweat slipped down his temple. "That… outfit…"

"SHUT UP!" Subaru snapped, his face burning. "It’s not like I chose this!"

"Hey, let’s all calm down," The shield guy said, raising a hand to ease the tension. He hesitated for a moment, glancing at Subaru’s outfit. "Though… I have to admit, it’s a bit… odd."

Subaru turned away, cheeks flushed, and muttered, “I know…”

“…Cute,” Naofumi thought, then quickly looked away, scanning the surroundings to distract himself.

“Where are we?” he asked, glancing around. “Is this… what I think it is?”

“Yeah. Looks like we’ve been isekai’d to another world,” The sword guy replied. He paused, briefly lost in thought, then gave a small shake of his head. “Anyway, we should introduce ourselves.”

“I agree. I’m Itsuki Kawasumi,” Itsuki said politely.

“Ren Amaki,” Ren added, his voice flat as he rested a hand on his sword, holding himself with quiet composure. 

Subaru and Naofumi exchanged a brief glance, then spoke at the same time.

“I’m Naofumi Iwatani.”

“MY NAME IS NATSUKI SUBARU!!!”

Their voices overlapped. Naofumi stood normally while Subaru struck a grand, theatrical pose, his spear thrust high toward the sky as though proclaiming himself to the heavens.

Then, abruptly, every voice fell silent. The three of them stared at Subaru, and even a few passing locals paused to watch. Subaru’s bravado crumbled, he slowly lowered his spear, dropping the pose as heat rushed to his face beneath his twintails. 

Ren said nothing. He just turned away, and stared at the empty air in front of him. He appears to be looking at something. 

“Hey, what’re you doing?” asked Itsuki while Naofumi nodded along. 

Ren stood there, calm and distant, his gaze fixed on empty space. Yet his eyes flickered with subtle activity, as though tracking something unseen. Subaru couldn’t help but wonder, what exactly was he looking at?

“What’s wrong with you three? That should’ve been the first thing you noticed,” Ren said, his tone edged with quiet disbelief. “Don’t you see the icon in the corner of your vision?”

Subaru blinked. He hadn’t noticed it due to his confusion, but now that Ren mentioned it, there was a faint symbol at the edge of his sight, so he focused on it. The icon expanded outward, showing his status.

[Natsuki Subaru]

[Class] : Spear Hero LV1

[Equipment] : Base Spear (Legendary Weapon)

Other-World Armor (???)

[Skills] : None

[Magic] : None

“Is...this a system?” Subaru muttered, staring at the glowing interface hovering before him.

“Level 1? That’s… not exactly reassuring,” Itsuki added, his voice tight with concern.

“Yeah,” Naofumi said, frowning at his shield. “I mean, what am I supposed to do with this?”

Subaru stared at his hologram. He was about to dismiss it when suddenly the text flickered. 

It...glitched. Purple static crawled across the screen, bleeding into the edges, causing the words to distort, reform, and break apart. 

[ERROR]

[SKILL TREE ACCESS – UNAUTHORIZED]

[FORCED OVERRIDE – MINUTE HAND OF THE DRAGON – UNLOCKED]

Subaru widened his eyes instantly. “What the...?!” 

The spear in his hand was suddenly engulfed in light. In a single heartbeat, the entire weapon began to reshape itself. When the radiance faded, it had transformed completely. Fresh metal had flowed seamlessly along the shaft, refining its form. The spearhead stretched longer, its surface turning faintly translucent as a soft inner glow pulsed within it. Near the base, a small circular ornament emerged, a pale red gem settling into the shaft as if it had always belonged there.

"Wh-What...just happened?" Itsuki's voice came from beside him, eyes wide. "Your spear...it transformed. How did you do that?"

“T-That shouldn’t be possible. You’re level one.” Ren’s voice wavered, his eyes widening in disbelief as his grip tightened around his sword.

Subaru couldn’t tear his gaze away from the transformed spear. To him, it was something mesmerizing, almost unreal. Its beauty stirred something deep within him, awakening a childlike sense of wonder he thought he’d long outgrown. His heart raced, excitement bubbling up again uncontrollably, as the reality of it all finally sank in, he had truly been summoned to another world. 

Subaru’s gaze stayed fixed on the spear, unable to pull away until a voice suddenly broke through the moment.

“This is… strange.”

Itsuki’s words were soft, laced with uncertainty. He turned the bow over in his hands, studying it with careful attention, the pristine white shaft, the delicate gold accents, the yellow gem set perfectly in place. Every detail was too precise… too familiar.

“What is it?” Naofumi asked, his tone steady but wary.

Itsuki didn’t respond immediately. His fingers traced along the elegant curve of the bow’s limb, feeling the smooth, almost unreal texture, as if confirming it was truly there. Only then did he lift his gaze, scanning the street around them.

“This bow…” he began slowly, his voice tightening, “it looks exactly like the legendary bow from Dimension Wave. The design, the craftsmanship, everything matches.”

He hesitated, eyes narrowing slightly. 

“But this world… doesn’t.”

Subaru tilted his head, curiosity replacing his earlier awe. “What do you mean?”

“In the game, the starting city is Melromarc. The heroes are supposed to be summoned inside a ritual chamber.” Itsuki gestured toward the open street, the unfamiliar buildings, the passing figures. “Not here. The architecture’s off… and even the NPCs look different.”

A quiet voice followed.

“Same here.”

Ren stood still, his grip tightening slightly around his sword as his sharp gaze swept across their surroundings.

“This sword is from Brave Star Online. I’d recognize it anywhere,” he said, calm but certain. “But that game had fixed geography, specific cities, and mapped regions. I memorized all of it.”

He paused, the weight of realization settling in.

“This place… doesn’t exist in any of them.”

Subaru blinked. “So…you’re saying your weapons are from your games, but the world isn’t?”

“That's exactly what I'm saying,” Ren said.

Itsuki nodded, still staring at his bow. “It's like someone took the weapons out of the game and dropped them somewhere else.”

Naofumi crossed his arms, a thoughtful frown on his face. “That's… weird. But also kind of interesting.” He glanced at his own shield. “I don't have a game to compare mine to. I just read about it in a library book.”

Subaru gazed down at his spear, spinning it around before stopping his spear against the ground.

“I’ve played games,” he said slowly, “but nothing like what you just described.”

He fell silent, thinking. Then, his eyes lit up. 

“Hey…just to be sure, let’s test something.”

The other looked at him, puzzled. 

“Who’s on the thousand yen bill?”

Subaru raised his spear upward and counted.

“One, two…”

“Yamaha Gotaro!”

“Yuda Masato!”

“Noguchi Hideyo!”

“Noguchi Hideyo!”

Their voices overlapped, united, yet completely divided. Silence fell like a dropped curtain.

Four heads snapped toward one another, confusion written plainly across every face.

“Who?!”

The word came out almost in unison.

Ren was the first to recover. His face settled back into its usual calm, though his eyes remained sharp, calculating.

“Let’s test further,” he said evenly.

A brief pause.

“Who is the current Prime Minister?”

The four continued their back-and-forth, talking as the afternoon light gently softened around them. Long amber shadows stretched across the cobblestone street, while above, the sky shifted from warm gold into a soft lavender near the distant castle. A few locals, a lizardman, and a catwoman paused for a moment to glance at them, then quietly went on their way.

Their discussion carried on, names, dates, fragments of pop culture, lines from history books, even the occasional song lyric. Every now and then, Subaru and Naofumi would exchange a small nod, a quiet spark of recognition passing between them as something clicked. The other two, however, could only stare, confused and silent.

Most answers were met with blank expressions and furrowed brows. With each exchange, the gap between them grew wider. At first, they thought they came from different cities… then different regions… maybe even different eras.

But as the conversation stretched on, one truth settled in, heavy and undeniable.

They were all from different worlds. 

───▽───

The weight of the realization settled over them, not spoken, but quietly understood. For a moment, no one moved. A gentle breeze drifted through, carrying the scent of unfamiliar flowers, as Subaru’s gaze fell to the cobblestones beneath hi-her feet.

His thoughts slipped, uninvited, to his parents. The memory struck without warning, like a blow he hadn’t braced for. The excitement he’d felt earlier dimmed, replaced by something quieter, heavier. His last moment with his mother, walking away without a proper goodbye, lingered painfully, tightening his chest until it almost hurt to breathe.

“It seems we’re all from different versions of Japan,” Itsuki said softly, staring into the distance. Then his eyes shifted toward Subaru and Naofumi. “…Though Subaru-san and Naofumi-san’s worlds seem…closer. More similar than ours.”

Itsuki’s voice rang clear in the stillness. Subaru looked up sharply, pulling in a slow breath. He shoved everything down, locking it away deep in his chest where it could wait, where it had to wait.

Then he forced a grin onto his face. Because Natsuki Subaru had to keep smiling. Because if he didn’t… he wasn’t sure what might spill out instead.

Naofumi was the first to break the silence, letting out a long, steady breath. He shifted the shield on his arm and glanced toward the wider street ahead.

“Well, we can’t stand here forever,” he said. Not impatient, just stating a simple fact.

Ren looked at him, then followed his gaze down the street.

“He’s right,” Ren said. His voice had returned to its usual flat tone, though it carried a quieter edge now. “We need shelter before nightfall. Food. And information.”

Itsuki gave a small nod, adjusting the bow at his back. “Right.”

“Alright then! Let’s go!” Subaru suddenly burst forward, pointing down the road before turning back with a bright, almost defiant grin.

Naofumi and Itsuki returned it without hesitation, something warm and steady in their expressions. Ren blinked, caught off guard for a brief second, then, almost reluctantly, a small smile found its way onto his face.

“…Yeah.”

Subaru took the first step, and the others followed. Their footsteps echoed softly against the cobblestones, light but certain.

The city stretched out before them, taller buildings casting long shadows, unfamiliar faces passing by without a second glance. It was a world that didn’t know their names, didn’t care where they had come from.

And yet, side by side, they walked forward together, four strangers from four different worlds, stepping into the unknown.

Notes:

Hehehe...(^-^)/

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