So tired…
Unable to move or speak, Shirou Emiya was overwhelmed by exhaustion.
So sleepy…
The emptiness of his mind, the damage to his soul—he couldn't even cling to his last memories of the people he cared about.
So dark…
It felt as if the entire world had been swallowed, devoid of sound, devoid of light. Before Shirou's eyes lay nothing but pitch-black darkness.
It's like sinking to the bottom of the ocean…
Even breathing became a struggle.
Is this… death?
Like vibrant flowers steadily wilting away in endless darkness, Shirou felt as if he lay upon a swamp, his body gradually sinking, being devoured by the abyss.
His remaining consciousness started to fade. He no longer wanted to think.
He only wished for sleep.
Just to sleep…
"How can you even think of sleeping at your age? You haven't finished fulfilling our contract!"
At the instant before Shirou's consciousness completely vanished, a mechanical yet furious voice suddenly erupted in his mind.
"Guh—haah—!"
Air rushed violently into Shirou's lungs as his eyes snapped open in shock. He sat bolt upright, frantically looking around at his surroundings—
A clump of soil abruptly struck him in the face, knocking him back down just as he drew his first desperate breath.
"You're… not dead?"
A voice Shirou knew all too well spoke incredulously from above. He tried turning his head, but his body refused to obey. Still, he soon caught a glimpse of who was addressing him.
Blue hair cascaded from above. Shirou's vision, still blurred and weak, sharpened instantly, pupils shrinking in disbelief.
Why is she still alive…!?
In his last memory, his reverse-blade katana had been pressed against her neck. She couldn't possibly have evaded or survived.
Shirou squeezed his eyes shut, forcing himself to recall the details of that final battle.
At the very moment he'd nearly severed Esdeath's neck, a strange, otherworldly glow had erupted beneath their feet. After that flash, Shirou had no further recollection.
That had been his final strike, a blow that burned everything he had left.
"A pierced heart, not breathing for three days, yet you're still alive. If your body wasn't so obviously human, I'd suspect you were a modified being," Esdeath remarked casually, pulling Shirou from the ground.
Only then did Shirou realize exactly where he'd been lying.
It was a shallow pit, and at the head of it stood a makeshift stone marker, crudely engraved:
[Here Lies Shirou Emiya, a True Warrior.]
"Don't worry about it. You were someone worthy of my respect, a warrior with a golden spirit deserving a proper grave—even if we were enemies," Esdeath explained calmly, lifting Shirou into her arms and carrying him gently toward a nearby, hastily-built shelter.
"Why… didn't you kill me?"
Though Shirou was entirely helpless, he could still manage a weak voice.
"If this had been my first day stranded on this island, seeing you alive would have made me sever your head without hesitation," Esdeath replied bluntly, not bothering to hide her intentions—just as Shirou's own eyes openly displayed a burning hostility, despite his helpless state.
Humans were social creatures; no one could endure complete solitude—not even Esdeath, the Empire's strongest warrior. Three full days without a single living soul to speak to had taken their toll. She didn't know if they'd ever escape this island, and though she was confident in enduring isolation for a short while, she feared the madness prolonged solitude would eventually bring.
Thus, upon witnessing Shirou's miraculous resurrection, Esdeath's first instinct was not to kill him, but to save him—despite the clear hostility emanating from him.
Of course, if Shirou wished to fight her once more, Esdeath would eagerly welcome the challenge.
At the very moment Shirou awoke, the flame-like marking that had appeared on his forehead earlier rapidly shrank away, leaving behind only a small fragment.
Shirou had no idea what it was—and neither did Esdeath.
Yet Esdeath instinctively wished to understand it. Somehow, deep within her, she felt she could manifest similar markings.
These markings—a [Demon Slayer Mark]—were signs of greatly enhanced power for those practicing Breathing Techniques. To manifest a Mark, one's body temperature must rise above 39°C, accompanied by a heartbeat over two hundred beats per minute, a condition that left the body practically burning. Surviving this extreme state determined whether or not a Mark could appear.
Yet the Mark was not without cost. Users who awakened their Marks rarely lived beyond the age of twenty-five, as it rapidly consumed their lifespan.
But Shirou's Breathing Technique was uniquely intertwined with his Magic Circuits, making the usual prerequisites inadequate. Mere fever and elevated heart rate were insufficient for him—only in the extreme throes of battle could Shirou awaken his own Mark.
Among all Breathing Techniques, Sun Breathing was the origin and pinnacle, developed by the legendary swordsman Yoriichi Tsugikuni. Unable to master Sun Breathing due to its intense nature, other swordsmen adapted it into the foundational styles: Water, Thunder, Flame, Stone, and Wind.
Even Shirou's self-created Sword Breathing and Kokushibo's Moon Breathing could not transcend the original Sun Breathing's essence.
Sun Breathing could channel the power of the sun itself, coating blades with a blazing red aura—the legendary Crimson Blade, devastatingly lethal to demonic beings.
This was precisely why Shirou's reverse-blade katana—though not a Nichirin blade—had blazed crimson-red in his final moments.
But did using Sword Breathing mean Shirou was denied access to the sun's power?
The answer was clear:
No.
All Breathing Techniques inherently drew upon the sun's energy, though Sun Breathing accessed it most directly and powerfully.
In his final moments, Shirou—his mana, life force, Mark, and even his soul burning as one—had become like the sun itself falling to earth, blazing uncontrollably.
And no matter how powerful Esdeath's ice, how absolute her frozen world…
The last embers of a falling sun could never be contained by mere ice.
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T/N: Im guessing his mark looks like yoruichis since he got it with sun breathing stuff or something idk ifhashfas ALSO HOW DID SHE GET TRAPPED ON AN ISLAND