Re:Zero starting from zero with the knight of betrayal

by GillySilly

Summary:

This came from a random idea of mine, if Subaru summoned Mordred, because i like Subaru and i like Mordred

Notes:

This work used AI to help fix grammatical errors and enhance words, since I'm not the best at this type of thing, its my first work and thank you for reading

Chapter 1: Prologue, A Flower drenched in red

Subaru stared at the apple vendor… no, the appa vendor, as it was called in this world. He had returned—his clothes pristine, with no sign of the damage he had suffered. No blood stained his outfit. He still held his grocery bag in one hand, but in the other, a single white flower lay there. Just as he said it would happen—he had returned from death.

Minutes ago

Subaru felt powerless as he stared at “Satella,” who had fallen beside him—the pool of blood staining her white clothes. Her hands were intertwined with his. And at that moment, he made a promise.

“I will definitely―Save you.”

But it was just an empty promise—something he couldn’t fulfill. The futility of it all was just a mockery of Subaru. Natsuki Subaru knew the truth: he wouldn’t survive this. His fate was already sealed. He was just as useless as always.

“So, you’ll just accept this? Are you really going to accept your powerlessness and give up?”

The voice didn’t come from the desolate surroundings, but from inside his head. Maybe it was the last shard of pride he still had—but no amount of pride could change the truth: he was powerless.

“If you had a powerful warrior by your side—someone to share your burden, to stand and fight beside you—do you think things would have ended differently? If you can’t do it alone, then seek help. Sometimes, the burden on your heart is too heavy for one person to carry. A late student of mine only realized this when it was too late.”

It was a strange question, but one Subaru entertained anyway. If he had someone—anyone—to help him, someone who had what he lacked… maybe it would be different. Maybe, together, they could save Satella. Someone to share his burden. Maybe, with their help, he could meet the expectations he put on himself and finally reach his father—become someone his parents could be proud of, even if it meant relying on someone else.

“So, what are you waiting for? Ask for it. Ask for help, and I shall help you, Natsuki Subaru.”

With the last remaining strength Subaru could muster, he asked:

“Help… please, help me.”

“If you ask with such conviction, what kind of monster would I have to be to say no?”

And at that moment, Natsuki Subaru died.

Chapter 2: The land of those free of sin

Confusion.

If he could put his feelings into a single word, it was that.

Subaru stood at the edge of the tower, staring down at the world below. A sea of pink stretched endlessly—countless flowers weaving the land into a living tapestry. Beyond the horizon, a vast forest swayed in the sunlight. Warm rays kissed his skin. Sweet fragrance drifted on the air, blossoms mingled with the smell of summer.

A paradise. Untouched. Pure. So peaceful it smothered the restless turmoil clawing at him since his last encounter.

He had died.

And yet—no panic. He didn’t scream. Couldn’t. Even though he should.

All he could do was stare. Let time slip past.

Seconds. Minutes. Hours.

Subaru was lost, drowning in beauty, the vision searing itself into his mind.

“Beautiful, isn’t it?”

The voice jolted him.

“Sometimes I lose myself in it too. A paradise so flawless, unmarred—beyond anything humans could imagine. No people. No beasts with wisdom. Only endless flowers, crystal streams, and the fairies that make their homes in the ponds.”

Subaru turned. A man sat beside him—when had he even arrived?

But the voice… yes, he knew that voice. The one that had whispered to him on his deathbed.

The stranger was dazzling. Handsome. Calm. White hair spilled down his back, catching the light in a shimmer of rainbows. His robes were silk, pure as snow. A faint floral scent clung to him, carried on the breeze.

Subaru’s voice cracked.

“I… I died, right? Is this heaven? Are you God? Were you the one who summoned me into that world?”

A loud, stupid, heartfelt laugh. The kind that stripped away all his elegance in a single breath and left behind… a smug, infuriatingly punchable face.

Subaru’s cheeks burned.

“Yes, you died,” the man said, still grinning. “But don’t worry. The one who summoned you will handle that. And no, this isn’t heaven. And I am definitely not God.”

He stood, stretched lazily, then swept his arms in a dramatic flourish.

“Allow me to introduce myself. I am the Mage of Flowers, court wizard of Camelot. The one before you is Merlin. Though I suppose, Subaru… you know me better as Magi☆Mari.”

Silence.

The wind brushed against the tower walls.

Subaru stared. Unblinking. Disbelieving.

“It… it can’t be. YOU?”

“Indeed,” the man said, his grin growing even wider. “The legendary magician of Arthurian fame. That’s me. Most of the stories you’ve heard are probably true. Now, as I was saying, we must discu—”

“Magi☆Mari?!” Subaru’s voice cracked like glass. “The pure, beautiful elf V-tuber Magi☆Mari?! My first love was YOU?!”

Merlin coughed into his fist, face suddenly awkward.

“Well… yes. I did start V-tubing to pass the time. Eternity in a tower gets terribly dull. But we really do have more urgent matt—”

He never finished.

Because Subaru lunged.

The paradise that had soothed his soul moments ago now only stoked his fury. Red bled into his vision as his hands clamped around Merlin’s throat.

“Give me back my feelings! The thousands I spent on merch! The hours cheering for you! Your laugh—your laugh pulled me out of the darkest pits of my life! My heart thumped for you—AND IT WAS ALL A LIE! ALL YOU!”

some time later

The sun had sunk. Stars glittered in the winter sky, and the crisp autumn air filled the tower.

Two figures sat at a table. Subaru, sulking, arms crossed, glaring at nothing. Merlin, sheepish, scratching the back of his head.

With a wave, Merlin made two flowers bloom on the table. They dissolved into glittering light, leaving behind cups of steaming, fragrant tea. He slid one toward Subaru, who turned away with a sharp huff.

Merlin sighed, pinching the bridge of his nose.

“Subaru-san, I get it. You’re angry. You have every right to be. But we need to talk about serious matters. So please—let’s set aside our differences, just for now. We need to discuss your… ‘otherworldly situation.’”

Subaru grudgingly gave the smallest of nods.

Merlin dabbed at nonexistent sweat before continuing.

“Well then. To start: you were transported to another world. And you died. Rather gruesomely, I might add. But that isn’t the important part. What matters is this—you were granted a special ability. Just like the novels you’ve read, the one who summoned you gave you something unique.”

Subaru’s eyes widened. “An… ability?”

“Patience, patience,” Merlin said, lifting a hand. “Your ability is this: whenever you die, you return to a previous point in time. Think of it as a save system in one of your games. The catch? You don’t control the save point. The one who summoned you does. So relax, leave the details to them. Oh, and—very important—you mustn’t tell anyone about this. Your sponsor would sooner kill you than let the secret slip.”

“Who even is this myste—” Subaru’s fists clenched, frustration bubbling.

“Ah, yes. The obvious question.” Merlin cut him off with a smug grin. “You’re thinking: ‘I’m weak. Even with this power, what can I accomplish?’ A fair point. Which is why I came here. To help you find an ally. Someone powerful. Someone to make up for what you lack.”

Subaru’s expression eased slightly. “A powerful ally would be… wait a second.” His eyes narrowed. He slammed his palms against the table. “You’re dodging me again. Who summoned me?!”

Merlin’s grin only widened.

“Who is your ally, you ask? A heroic spirit! Spirits of heroes, their legends given form. And not just anyone—one of the Knights of the Round Table! Imagine it, Subaru: a knight dedicating their sword to you. Perhaps even King Arthur himself!”

“You’re STILL not telling me who summoned me!”

“Oh, that?” Merlin waved dismissively. “Simple question, really. But… oh dear. Our time is nearly up. A pity. I’m sure you’ll learn soon enough.”

With another casual flick, a white flower appeared in Subaru’s hands, along with a slip of paper.

“To summon your heroic spirit, find a secluded place. Crush the flower, recite the chant. The knight most compatible with you will appear.”

And then—like a channel flipping in his mind—Subaru’s vision snapped.

The smug wizard was gone.
And standing before him once again—was the appa vendor. he returned.

Subaru blinked, the weight of betrayal still heavy in his chest.

His first coherent thought: I hate Merlin.

 

Subaru could now, without a shred of doubt, declare this the worst day of his life.

Seriously. This was rock-bottom.
No way it could get any worse.

He had lost everything —
and when he said everything , he meant everything .

His memories? Ruined.
Her smile? Shattered.
Her sweet laugh as she thanked him for his donations? Poisoned.
His room, his poster, the shrine-like shelf filled with merch? All tainted!

And the culprit… was him .

Of all people—of all faces—why did it have to be HIM?!

On this day, Natsuki Subaru lost something fundamental. A piece of himself he would never, ever get back.

But—there was no time to mope.

He needed to summon his knight. His ally. The one who would help him save Satella.

Because that’s what Subaru did, wasn’t it?
Even when the universe spat in his face, even when life took everything he cared about and stomped on it, he still— still! —reached for any lifeline he could find.

And damn it, he was going to grab this one.

Ignoring the vendor’s confused stare, Subaru bolted into a deserted alley.

His heart pounded. His stomach twisted. His throat burned with bile.
The sense of betrayal gnawed at him like a rabid dog, but—no. Focus. Focus!

At least… at least he was about to summon a Knight of the Round Table.

A knight . Of the Round Table ! That was awesome, wasn’t it?!

Lancelot, the Knight of the Lake. If he got him, the mysterious assassin could pack their bags.
Or maybe Gawain, the Knight of the Sun. Bit of a Puck 2.0 problem, but hey, still a power boost!
Or—oh man, what if he got the big one? The King of Knights, Arthur himself?! With the legendary Excalibur flashing in his hand?!

It was like pulling a limited gacha banner. Except this time, no 3-star junk to clutter the pool. Nope. Every pull was guaranteed fire. Every knight a certified powerhouse.

…Right?

Right?!

They were heroic spirits, after all!
Heroes. Legends. Knights.

He crushed the white flower.

And froze.

Because the damn thing was bleeding.

“What the hell—why is the flower bleeding?!”

Crimson liquid spilled across the ground, sketching out a ritual circle like it had done this a thousand times before. The petals dropped into place, glowing as if they’d rehearsed it.

Subaru’s brain screamed at him to run, but his mouth moved anyway.

He recited the chant.

“Heed my call. My will creates your body,
And your sword shapes my destiny.

If you heed the call of Avalon, obey my will and reason—
Then answer my summoning!

I hereby swear to uphold all that is good in this world,
And to defeat all evil within it!

Seventh Heaven clad, by the words of power—
Come forth, Knight of the Round Table!”

Red flowers exploded in his vision.

And then—just as suddenly—gone.

Scattering into glittering crimson motes.
Mana. Probably. Definitely magic-y enough to count.

When the haze cleared, a knight stood in the circle.

Small.
Clad head to toe in armor traced with red lines.
A pair of sharp horns jutting from the helm.

The knight planted their sword into the earth with a heavy thud.

Then—like some kind of sci-fi magnetic trick—the helm merged into the armor, sliding away seamlessly.

And the face revealed beneath was… a girl.

“I am Mordred, the true heir of Arthur Pendragon.
So I ask you—are you my Master?”

Subaru’s mind blanked.

…Mordred.

As in, that Mordred.
The one who killed her own dad—King freaking Arthur.
The Knight of Betrayal.

Subaru’s soul left his body.

Of course. Of course! Out of all the legendary knights, all the shining heroes of Camelot, I get the family backstabber deluxe edition! The guaranteed disaster pick! The gacha pull everyone rerolls to avoid!

Wouldn’t she be the worst possible Heroic Spirit to have?!

Notes:

so it comes, the first 'real' chapter of this fic, hope you guys enjoy it