The sound hung in the ash-choked air of Fuyuki, a tiny, vibrant anomaly against the backdrop of desolation. Chumimi~ It was a sound of pristine mechanics, of a perfectly balanced gyroscope spinning in a vacuum. It came from him.
Kim Min-jun lay paralyzed by pain, his consciousness tethered to the ruined landscape of his body, yet his entire awareness was funneled to the tip of his right index finger. The golden point of light there wasn't just illuminating; it was defining the space around it, warping perception like a lens. And the sound… it was the auditory expression of a fundamental law. Rotation. Incessant, infinite rotation.
As he focused on it, a wave of relief, so profound it was dizzying, washed through him. It was not healing. The agony in his ribs and back remained, a sharp, screaming fact. But the relief came from a different place—from the crushing despair, the hollow man's final victory. This sound, this light, was an absolute rebuttal. It was evidence that the entity had not simply tossed him into another meat grinder. It had given him a tool. A principle made manifest. He was not just a broken body in a graveyard; he was a broken body with a singular, undeniable power.
With the relief came a flicker of cognitive dissonance so sharp it cut through the pain. A geometric, personified power emanating from a spirit-like energy? A bizarre, specific sound effect?
No. It can't be.
The thought was absurd. A pop culture phantom from a life buried under trauma. The hollow man had occasionally consumed media in a passive, numbing way. Fragments lingered. The notion was ridiculous. This was the Fate universe, a realm of Thaumaturgy, Mystic Codes, and Heroic Spirits. This was serious, grim, a battle for human incineration. The idea of… Stands here was a tonal impossibility, a childish mash-up. The entity had spoken of potential, of tools. This was his reincarnator's "cheat," undoubtedly. A unique Mystic Code baked into his soul, his Origin perhaps made manifest. It just happened to have aesthetic and auditory similarities to something else. A coincidence. It had to be.
He pushed the bizarre comparison down, locking it away. It was a dangerous line of thought, a step towards madness he couldn't afford. He focused on the immediate, tangible reality: the Chumimi~ was a lifeline.
Concentrating through the pain, he tried to exert will upon the point of light. He didn't command it to fire, but to clarify. In response, the golden light intensified slightly, and the rotational hum deepened. A phantom sensation, not quite sight, blossomed in his mind. He perceived his own body from a new angle—not from his eyes, but from a point just behind and above his right shoulder. It was a perception of intent, of a presence that was both utterly him and distinctly separate. It was not a ghostly figure, but a concentrated field of golden, spiraling energy, anchored to him, its focus aligned with his fingertip. It was a limb he had never known he possessed.
Tusk. The name surfaced in his consciousness without fanfare, as natural as breathing. Act 1.
Understanding flowed into him, instinctual and clear. This was a projectile weapon, generated from his own fingernail. It was a physical bullet of crystallized rotational force. Its power was not raw explosive energy, but infinite penetration derived from its spin. It would drill. It would not stop. It was a tool for creating openings, for solving obstacles by removing them in the most direct way possible.
The warmth radiating from the Tusk-entity—no, from his ability—seemed to stabilize him. The bleeding from his back felt slower, as if the very cells around the wounds were being subtly agitated, encouraged to hold fast. The pain was still a white-hot furnace, but he found he could think around it now. He could plan.
First, he had to move. Lying in the open in a Singularity was a death sentence. Gritting his teeth, he used his left arm—his good side—to push himself up onto his left elbow. The world swam, and a fresh wave of nausea threatened to engulf him. He breathed in shallow, ragged gasps, each one a knife-twist. Slowly, agonizingly, he dragged himself behind the burnt-out husk of a sedan, its tires melted into puddles of black rubber. The crude cover offered minimal protection, but it was better than nothing.
From his new position, he peered out at the street. The silence was oppressive, broken only by the wind. Then, he heard it. A dry, scraping sound, like stone dragging on asphalt.
From around the corner of a collapsed convenience store, a figure shambled into view. It was a skeleton. Not a clean, anatomical model, but a grim, discolored thing, bones stained with soot and age, held together by flickers of malignant purple energy that glowed in its ribcage and eye sockets. It clutched a rusted short sword in its bony grip. Its movements were jerky, purposeless, yet it radiated a palpable sense of menace. A Familiar. A low-grade spiritual nuisance, but to a man with broken ribs and no combat training, a deadly threat.
A second skeleton appeared, then a third. They moved in a loose cluster, scanning the area with empty sockets.
Min-jun froze, pressing himself lower against the cold asphalt. His heart hammered against his broken ribs, sending fresh jolts of agony through his torso. He had no idea how effective Tusk Act 1 would be. Could it shatter bone? Would the rotational force simply punch a clean hole through a skull, leaving the rest of the construct animated? What if it just annoyed them? The sound of the shot, that distinct Chumimi~, would give away his position instantly. If he couldn't kill or disable them all quickly, he was done for. He was a maintenance technician, not a fighter. His directive was to support, to build, not to engage in open combat.
He opted for stealth, for the foundation's first principle: endure. He remained still, controlling his pained breathing, watching as the trio of undead shuffled past his hiding spot, their scraping footsteps fading down a side alley. The tension bled from him, leaving him trembling with weakness and relief.
He needed shelter, water, a place to assess his wounds properly. Using the car door frame, he hauled himself to his feet, leaning heavily against the metal. Black spots danced in his vision. He could only take small, shuffling steps, dragging his right leg which refused to bear proper weight. He moved in the opposite direction of the skeletons, towards what looked like the shell of a two-story residential house, its roof caved in but walls partially standing.
Every step was a marathon. The world narrowed to the next few inches of ground, the next breath, the constant, threatening throb from his back. The golden point of light on his finger had faded, but he could feel the potential humming just beneath his skin, a warm battery of defiant energy. He clung to that feeling.
He was ten feet from the gaping doorway of the house when the dry scraping returned. From behind a pile of rubble to his left, a single skeleton emerged, its head tilting, purple flames in its sockets flaring as it spotted him. It was between him and the house. Another scraped into view from the right, cutting off retreat. A third, likely from the original trio, appeared at the mouth of the alley he'd just passed.
They had him surrounded. They'd been lying in wait, or his slow, noisy movement had drawn them. It didn't matter.
Panic, cold and sharp, tried to seize him. He leaned against the car, his mind racing. He couldn't run. He could barely stand. Hiding was no longer an option. The directive to support, to build, was meaningless if he died here in the opening minutes. Sometimes, the foundation had to clear the debris before it could settle.
The skeleton directly ahead, the closest, raised its rusted sword and let out a silent, rattling shiver as it charged, its gait a lurching sprint.
There was no more time to theorize. No more time to worry about cross-universe aesthetics. This was survival.
Min-jun raised his right hand, his injured arm screaming in protest. He focused not on the mechanics, but on the principle. The need to break through. To create an opening. To rotate.
"Tusk."
The word was a whisper, a command to his own soul.
CHUMIMI~!
The sound was louder, sharper, a declaration. The golden point at his fingernail flashed brilliantly. There was no recoil. No muzzle flash. Only a brief, intense vibration up his arm, and a streak of gold, too fast to truly see, etching a line in the air between his finger and the skeleton's skull.
It was not a bullet. It was a drill.
The golden projectile struck the skeleton's forehead with a sound like a diamond-tipped bit hitting porcelain—a high, sharp CRACK-CHRRR. The rotational force did not explode the skull. It penetrated. A perfect, spiraling hole appeared in the frontal bone. The purple energy in the sockets flickered wildly, then snuffed out. The malignant force holding the bones together vanished. The skeleton didn't crumble; it simply de-animated, collapsing into a harmless pile of old bones, the rusted sword clattering to the ground.
The other two skeletons halted for a moment, as if processing the loss.
Min-jun didn't hesitate. The action had felt seamless, an extension of his will. He pivoted his hand, the movement sending fiery agony through his side. He targeted the skeleton on the right.
CHUMIMI~!
Another golden streak. This one struck the ribcage, drilling through the sternum and severing the core of the purple energy. The skeleton stumbled, its form losing cohesion, and collapsed.
The third skeleton, now alone, turned as if to flee. Min-jun, breathing in ragged, victorious gasps, lined up his final shot. He aimed not for the body, but for the spine at the base of the skull, a marksman's instinct he didn't know he had.
CHUMIMI~!
The shot was true. The spinal column shattered under the infinite rotation, and the final pile of bones clattered to the asphalt.
Silence returned, heavier now. The distinct Chumimi~ echo faded, replaced by the wind and the frantic beating of his own heart.
Min-jun slumped against the car, the adrenaline drain making his injuries scream anew. He was drenched in cold sweat. But he was alive. And he had fought.
He stared at the three piles of inert bones. The power… it was clean, efficient, and terrifyingly potent. The rotational principle wasn't just about physical penetration. It seemed to disrupt the spiritual energy animating the Familiars completely. A direct hit was an absolute kill on this low-level enemy.
His mind, the part of it trained for systems and logistics, began analyzing even through the pain. The projectile was generated from his own biological material—his fingernail. It required no external weapon, no ammunition he could run out of. The energy source seemed to be internal, tied to his own vitality and will. He felt a slight fatigue, but it was minor compared to the drain of his injuries. Could he enhance it? The entity had mentioned his core drives were his compass. His will to protect, to support. Would a stronger resolve create a stronger rotation?
And then, a new, electrifying thought connected.
Magecraft. This was the world of Thaumaturgy. Magical energy—Mana, Od—followed laws, was shaped by circuits and incantations. His Tusk was a manifestation of his soul, a Reality Marble in miniature focused on a single concept. What if he didn't just will it to fire, but channeled magical energy into the rotation? Could he augment the speed, the mass, the penetrative power? Could he apply other magical principles to it? Reinforcement to strengthen the nail-projectile? A simple propulsion spell to increase its velocity?
He was no magus. Kim Min-jun had no magical circuits in his first life, and this Chaldea-issued body was that of a normal human. But he was in a Singularity, a place flooded with latent mana from the distortion. And he had a ability that was, by its very nature, a form of pure, conceptual energy manipulation. Perhaps he didn't need traditional circuits. Perhaps Tusk was his circuit, converting his will and lifeforce directly into the rotational principle.
It was a theory, a wild hope. But it was a direction. A path from being a wounded man with a strange gun to being… something more. A supporter who could not just stand at the hero's back, but clear the path ahead of them.
With a grunt of effort, he pushed off from the car and hobbled the final few feet into the dubious shelter of the ruined house. The interior was a charred mess, but one corner was relatively intact, shielded by a fallen beam. It would have to do.
He half-fell, half-sat against a wall, his body screaming in protest. Exhaustion threatened to pull him under. But as he looked at his right hand, where a faint, golden shimmer seemed to linger around the index fingernail, he felt something he hadn't felt in two lifetimes: a cautious, hard-won sense of agency.
He had a power. He had a purpose. And he had just survived his first encounter in a burnt world.
The pain was still there. The danger was omnipresent. But for the first time since he awoke in Chaldea, Kim Min-jun, the would-be foundation, allowed himself a single, shaky breath that wasn't entirely dominated by dread. There was a sliver of something else. A forward momentum.
However, the adrenaline from the fight was ebbing, leaving the raw, grating pain of his injuries in stark, masterful control. He slumped against the charred wall, trembling from exertion and shock.
His right hand lay in his lap, palm up. He forced his eyes to focus on it, expecting to see a bloody mess where his fingernail had been violently launched. But there it was—his index fingernail, intact. A little paler, perhaps, as if drained of some vital essence, but whole and unbroken. No wound. No bleeding bed. He flexed the finger experimentally. A dull ache radiated from the fingertip up through his forearm, a deep muscular and spiritual fatigue, but the flesh was unharmed.
He hadn't shot his nail. He had shot with it. The projectile was a crystallized manifestation, a copy forged from the concept of rotation and the blueprint of his own body. The relief was immediate and profound. He wasn't going to run out of ammunition by mutilating himself. The limitation was elsewhere—in that deep, bone-tired ache in his arm. It felt like he had just finished an exhaustive, full-body workout using only that limb. The energy, the "charge" for Tusk, was drawn from his overall stamina, his will, and seemed to pool specifically in that arm. He had a limited number of shots before he'd be too exhausted to summon the power at all. Three shots had left the limb feeling heavy and sluggish, the golden warmth now a faint, dormant ember.
Good to know, he thought grimly. Ammo is willpower. Conservation is key.
He needed to move. This house was a temporary respite, not a fortress. The gunshots—or rather, the distinct Chumimi~ sounds—might have attracted more than just skeletons. Pushing through the pain with gritted teeth, he used the wall to haul himself upright. The rest and the minor victory had injected a sliver of stubborn energy into him. The bleeding on his back had congealed into a stiff, painful crust. He could move. Slowly. Awkwardly. But he could move.
He ventured back into the perpetual twilight of Fuyuki, adopting a shuffling, lopsided jog that was the best he could manage. He stuck to the shadows of broken walls and hollowed-out vehicles, his senses straining for the telltale scrape of bone. The act of moving, of having a purpose—find the Master, find the Servant—kept the crushing despair at bay. The pain became a mere background noise, a system alert he was learning to ignore.
The landscape was a monotonous hell of ash and ruin, making navigation guesswork. He followed the slope of the land downward, reasoning that the ley lines—and thus any significant spiritual activity—might converge in what was once the city center.
He heard the battle before he saw it. The clash of metal on metal, a sharp, resonant clang that was utterly foreign to the desolate soundscape. And a voice, young and strained, shouting with desperate determination.
"Mash! On your left!"
Min-jun quickened his pace, his injuries protesting vehemently. He rounded the corner of a collapsed bank building and saw them.
In a wider intersection, Mash Kyrielight stood, her body now encased in sleek, purple-and-silver armor, the great rectangular shield held firmly before her. She moved with a grace and power that was breathtaking, utterly transforming the shy girl he'd seen in the corridors. Before her, two skeleton warriors pressed their attack, their rusted blades skidding harmlessly off the shield's surface. A third, further back, was gathering a sphere of flickering purple energy in its bony hands—a caster variant.
And there, crouched behind a chunk of rubble, was Fujimaru Ritsuka. The boy's face was smudged with soot, his eyes wide but focused, fixed entirely on Mash. He was shouting directions, his voice a thread of human will holding the line against the surreal horror.
They were holding their own, but the caster skeleton was a problem. Mash was perfectly suited to defending against physical attacks, but a magical projectile from an unexpected angle could break their formation.
Min-jun didn't announce himself. There was no time. He raised his right hand, the ache in his arm flaring as he summoned the will. The golden point of light flickered at his ring finger this time—an instinctual choice, spreading the fatigue. He took a fraction of a second to aim, leading the target.
CHUMIMI~!
The golden drill streaked across the intersection, a line of pure, penetrating intent. It passed just behind Mash's shoulder, a whisper of harmless golden light to her, and struck the skeleton mage directly in the center of its conjured energy sphere.
The effect was instantaneous and violent. The rotational force drilled into the unstable magic. The purple energy sphere imploded, then detonated in a crackling burst of voidal light, obliterating the caster skeleton into fragmented, blackened shards.
The remaining two skeletons, distracted by the explosion, faltered. It was all the opening Mash needed. With a powerful shout, she swept her shield in a wide arc, shattering both creatures into piles of bone.
Silence fell, heavier than before. Mash stood panting slightly, her shield lowering a fraction as she scanned for new threats. Ritsuka slowly rose from behind his cover, his gaze sweeping the area until it landed on Min-jun, still standing in the shadow of the broken wall.
Recognition, then profound confusion, washed over the boy's face. "You… you're from Chaldea! The maintenance guy! I saw you in the halls!" His eyes were wide with a mixture of relief at seeing another human and utter bewilderment at the context. Then his eyes darted to the space beside and slightly behind Min-jun's right shoulder. He pointed, his expression one of innocent curiosity cutting through the horror. "Whoa… what's that pink thing? It's… spinning?"
Min-jun felt it. The presence of Tusk, now that he'd manifested it, was subtly visible. Not as a full humanoid form, but as a localized warping of light and space, a shimmering, golden-pink vortex of energy that hovered near him, humming with a soft, rotational frequency. To someone with even latent spiritual perception like a Master candidate, it would look like a "pink thing."
Mash's head snapped towards him, her golden eyes now sharp with analytical focus. "Senpai, be cautious! That spiritual phenomenon… it's attached to him, but its nature is unclear. It's not a Servant, nor a standard Familiar."
Min-jun limped forward into the intersection, his movements clearly pained. He held up his right hand in a placating gesture. "It's not hostile. To you." His voice was rough from disuse and pain. He looked at Ritsuka, then at Mash, offering a slight, weary nod. "My name is Kim Min-jun. Chaldea Engineering. And this," he gestured with his chin towards the shimmering vortex, which pulsed slightly in response, "is my ability. For lack of a better term."
"Ability?" Ritsuka asked, stepping closer, his fear seemingly overridden by a natural, empathetic curiosity. "Are you okay? You're hurt pretty bad."
"I'll manage," Min-jun said, though the statement was undercut by a wince as he adjusted his stance. "The explosion at Chaldea… I was caught in it. Woke up here. This 'ability' woke up with me." It was a simplified, functional truth.
Mash approached, her shield still held but not raised aggressively. She studied him, then the shimmering Tusk. "Its energy signature is unique. It appears to be a conceptual weaponization of kinetic rotation, generated from your own spiritual framework. A form of innate Mystic Code… or perhaps a Reality Marble of extremely limited scope." Her tone was that of Dr. Roman's pupil, analyzing data.
"You can call it Tusk," Min-jun said, the name feeling more natural now. He looked at Ritsuka. "You're the Master candidate. Fujimaru. And you're Mash, the Demi-Servant. Chaldea's last line of defense. My job was to maintain the systems that kept you alive." He met Ritsuka's eyes, a flicker of his directive solidifying into words. "That's still my job. I'm not a fighter. Not like her. But I can support. I can clear obstacles. Like that caster."
Ritsuka's face softened. He saw the severe injuries, the clear pain, but also the steady determination in Min-jun's eyes. He'd just seen this man take a precise, impossible shot to save them. "You saved us back there. Thank you." He offered a small, genuine smile. "I'm Ritsuka. This is Mash. We're… trying to figure out what's going on and find a way to fix it."
The simplicity of the boy's statement, his immediate acceptance and gratitude, struck Min-jun deeply. This was the core he was meant to support. Not a legendary hero, but a good, scared kid trying to do the right thing.
A dry scraping sound echoed from a side street. Two more skeleton warriors emerged, their empty sockets fixed on the group.
Mash immediately moved to interpose her shield. "Senpai, behind me!"
Ritsuka tensed, but before he could give an order, Min-jun was already moving. The fatigue in his right arm was significant, but he pushed through. He raised his hand, the ring finger already bearing the faint, ready glow. The shimmering vortex of Tusk solidified its hum.
"Let me handle these," Min-jun said, his voice low. "Conserve your strength, Mash. You'll need it for bigger threats."
He took a pained but steady stance. The skeletons charged. He exhaled, focusing the intent, the need to protect the two behind him, to be the first line of the foundation.
CHUMIMI~!
The fourth shot. The golden drill lanced out, striking the lead skeleton in the clavicle, spinning through bone and spiritual bindings, dropping it instantly. He shifted his aim, the movement fluid now, an extension of his will.
CHUMIMI~!
The fifth shot took the second skeleton in the pelvis, severing its central structure. It crumpled mid-stride.
The Chumimi~ echoes faded. The golden vortex beside Min-jun dimmed noticeably. His right arm now hung at his side, trembling with profound exhaustion, feeling like a dead weight of lead. He'd likely reached his limit for now.
He turned back to Ritsuka and Mash. Ritsuka was staring, not in fear, but in awe. "That was… incredible. You just… drilled them."
Mash was looking at him with new respect. "The precision and spiritual disruption efficiency is remarkable, Mr. Min-jun. It is an excellent support ability for eliminating secondary threats."
Min-jun gave a tired nod. "It has its limits. I'm… tapped out for a bit." He gestured to his injuries. "And I'm not exactly in top form. But I can move. And I know this facility's systems better than anyone here. If we need to find a power source, stabilize a ley line, or just not die in a collapsing building, I'm your man."
Ritsuka's smile returned, brighter now. He stepped forward, offering a hand—not to shake, but to help support Min-jun's good side. "Then we're glad to have you, Mr. Min-jun. Let's find a safer place to talk. And… see if we can find something for those wounds."