Archive of Our Own

The path up the mountain was steep, and every step Izuku took threatened to be his last. His heart was erratic from pushing himself past his limit, lungs burning as the frigid air entered his nostrils. The snow was cold as it drifted lazily from the cloudy sky, pulling him under its lull as it soaked through his clothes and down to the bone.

His stomach was hollow with hunger, but he forced himself forward. 

Izuku almost didn’t fully register any of the pain, his mind caught up in replaying the same moment over and over with each step. If anything, the pain in his heart hurt more than his body being on death's door.

“Aw you poor useless child– what are you going to do, cry? Cry for your mother.”

That demon, with features as pale as the snow and eyes that were a glowing blood red, stared down at him icily, but not without a smirk on his lips. Clutched in his veiny hand was his mothers neck. His smile widened as his claws slowly tightened, puncturing her skin. Rivulets of blood dripped down his fingers, and his mother gave a sudden violent lurch.

“N-no! Let her go–,” Izuku had cried out, grabbing his hatchet with clammy fingers as he pushed himself from the floor. 

He had tried to fight that monster, but in the end was left slumped against a tree, hatchet buried next to his head where it had barely missed his neck. Through his blurry gaze he caught his mother shrieking as she struggled violently against the demon’s hold. 

He had never heard her scream like that before… The sound haunted him, echoing around his head as he pushed his legs harder. Through the weather, he could make out a faint light coming from a shack. Smoke curled lazily from the chimney, a thin promise of warmth. 

Next thing he knew, though the haze there was a man dressed in black, a sword gripped in his hands. His scarf billowed behind him as he stared the demon down with sharp yellow eyes. Izuku couldn’t make out what happened next, he must’ve hit his head pretty hard, but when he came to, the man in black was kneeling before him. “That was your mother right?”

Izuku nodded, head throbbing as he tried to maintain eye contact. The man cursed, before yanking his small body up by his collar. That seemed to snap Izuku out of his daze, because when his senses returned, his mother was nowhere to be seen. “W-wait, what happened to her!? Where is my mom,” he yelled.

That's when the man, Aizawa, a demon slayer, had explained it to him…

The sickening truth. His mother had been turned into a demon.

Aizawa’s instructions were the only thing keeping his legs moving.

“Find Yagi. Tell him All for One has attacked again. And tell him about your mother.”

Per his directions, the elder demon slayer lived in the north mountains surrounded by tall pines, and Izuku desperately hoped this was the place. He stumbled toward it, each breath a ragged wheeze, until his trembling hand pushed against the wooden door.

Inside, a tall man sat by a fire. The flames bathed his thin frame in gold and shadow, broad shoulders hunched and a mask obscuring most of his face. His head turned sharply at the intrusion, and his masked gaze locked on the boy who staggered through the doorway, immediately grabbing a sword that looked like the one the other man carried.

It had to be him, Yagi.

“All… for One…” Izuku rasped. “Aizawa told me… to come here. He said… tell you… All for One has attacked.”

The sword slipped from the man’s hand, clattering against the floor. In two strides, he was at the boy’s side, catching him as his knees buckled.

“You’re hurt,” the man said, voice tight and urgent as he clutched Izuku’s failing body. 

But Izuku wrenched free of his grip and collapsed forward. His palms slapped against the floorboards, and then he bowed until his forehead pressed hard against the wood.

“Please,” he begged, his voice raw and cracking. “Train me to become a demon slayer.”

The man above him froze. The fire popped in the silence as Izuku submitted before him, trying his hardest to cling to consciousness until he got an answer. For a long moment, it never came, but then a deep voice answered him.

“This path will scar you. It may even kill you. It is not–”

“I don’t care!” Izuku shouted, lifting his head. His determined eyes shone through the tears. “If I do nothing, my mother is gone forever! And even if she is dead, I want to make sure nobody gets killed ever again! Even if I die trying, then at least it won’t be for nothing.”

Only then did he truly look at the man before him. The firelight flickered across the carved mask he wore– an animal’s face in the likeness of a rabbit, its features hollow and a bit creepy. Two ragged tufts of golden hair jutted from either side, framing the mask and concealing any trace of the man beneath. The sight made Izuku’s stomach tighten and he shrank back instinctively, unsure what sort of person he had just thrown himself before.

Slowly, Yagi lowered a scarred hand gently on Izuku’s shoulder, heavy with both burden and promise. “…Very well,” he said at last, tone solemn. “If you are certain you want to carry this burden, then I will train you.”

The words unraveled what little strength Izuku had left. His body shook with sobs, grief and exhaustion crashing together with the fragile spark of hope that had finally taken root. The world blurred around him, his vision tunneling. Just before the darkness claimed him, he felt warm, strong hands catching him, holding him with surprising gentleness. That warmth lingered as his last tether to the waking world, a promise that he wasn’t alone.

The days that followed blurred into a rhythm of hardship. Izuku had taken two weeks to recover his strength from the biting edge of hypothermia and acute malnutrition. He felt restless the whole time, his dreams consumed by memories of his mother being taken and her screaming. Izuku wasn’t sure if she was dead or alive, but all he knew was that he would make things right.

Once healed, his training began.

Now every dawn, Yagi’s booming voice pulled Izuku from restless sleep, and sent him straight up the mountain where he was forced to make his way back every day. Except this was no ordinary stroll he would make back home when he traveled to and from town. Every day, his master would set new traps for him to clear, the intensity increasing from Izuku tripping over ropes, to knives being hurled at his face that he had to dodge or get skewered. By the end of the day, his legs trembled and his lungs screamed from acclimating to the high altitude. 

But he progressed, he got stronger, until eventually he moved on to sword training.

And just like that, it was as if the last few months of running down the mountain had been child's play. Every swing of his blade carved new blisters into his hands and made his biceps scream as he swung it over and over until he was sure to collapse. 

“Now, do two-hundred more,” his master would say in response.

Toshinori Yagi, as he came to find out, was relentless as an instructor. Yet, when the sun dipped low and the boy’s body finally failed him, there was always a softer side waiting. A warm bowl of rice and fish pressed into his hands. His torn haori mended with clumsy but earnest stitches. A heavy blanket drawn up around his shoulders during the cold nights while his teacher curled up on the opposite side of the room. He kept his face hidden away in the dark, the only stimulus reaching Izuku’s senses were the ragged wet coughs he let out.

Izuku had deduced that the man was sick with something, but he never talked about it.

Tonight was another quiet evening save for the crackle of the fire. Izuku cradled a chipped bowl in his hands as he ate what Yagi had made for him, a simple fish stew from what Izuku had caught in the river earlier that day. Across from him, his master sat half-way out the open door, seemingly lost in thought or in the stars.

Izuku’s gaze kept drifting to him, pondering what his master was always thinking about that kept him so quiet sometimes.

During the night was when Izuku thought about a lot of things too. Yagi had let him keep a journal for himself, which was where most of his thoughts went. Izuku had always found that if he could just get his worries onto paper, it helped him process the everyday trauma a bit better. So from the second week of training, he kept a log of every training exercise, the time of every meal, and of all the memories from before he came to live with Yagi.

Izuku wouldn’t let himself forget. In fact, he was sure nothing could ever make him forget that day, his mother, or All for One.

He raised his chopsticks to take another bite, but stopped before they reached his lips. Izuku took in his master’s ‘face’ once again. The red and black paint chipped with age. It was strange– the mask had become such a constant presence that Izuku almost thought of it as his master’s true face. And yet, Izuku couldn’t shake the desire to see the man underneath.

The thought of seeing Yagi’s real face felt like crossing a threshold, like finally being trusted with the part of him no one else was allowed to know. The mask was a wall, and Izuku desperately wanted to be let past it, even if what he found frightened him.

The question slipped out before he could stop himself.

“Master,” Izuku’s voice was hesitant. “Why do you wear that mask?”

It was subtle, but Izuku noticed the way his master’s shoulders stiffened at the question.

“It is a warding mask,” he said at last. “I carved it myself, years ago, and placed charms onto it. It serves as protection against the demonic. It has kept me alive longer than I had any right to expect.”

Izuku nodded, chewing on the explanation, but something still pricked at him. His brows furrowed. “I see… but then…” He hesitated, gathering the courage to continue. “Why do I not have to wear one?”

The silence stretched, heavy, before Yagi turned his head to face him.

“Let me tell you a story,” Yagi said, patting the space beside him as he looked back toward the night sky. Izuku settled next to him, bowl in hand, eagerly searching above for whatever his master was looking at. 

“There is a reason I took you on as my apprentice,” Yagi said, his voice carrying the weight of memory. “When I was a young man, I became the student of a master demon slayer. Her name… was Nana Shimura. Just as you and I, she too had been trained by one master. This role, one teacher, one student, has been passed down for generations.”

Izuku leaned forward, hanging on every word.

“It is not merely a swordsmanship we pass on,” Yagi continued. “But it is a duty. It is Sun Breathing, the first style, born from the man who understood the demons’ greatest weakness. Yoichi Shiguraki. He observed how sunlight burned them, how it reduced even the strongest of their kind to ash. From that truth, he forged a style that mirrored the sun’s strength, its relentlessness.”

Yagi’s voice softened, the hard edge of his lesson easing into something gentler. “That is why you do not need the mask when you are on this mountain. I used that very skill to ward them off. So don’t worry, you are safe here.”

Izuku blinked, memory stirring. 

So that’s what he had seen. The first night of the New Year, when he woke to the sound of coughing, only to find Yagi standing alone outside the hut. The firelight had painted his frail frame in gold as he moved with a slow, deliberate rhythm. Each step was graceful, flowing into the next, his arms cutting the air in sweeping arcs like rays of light as he danced.

Even then, Izuku had felt something thrumming in the air, a warmth that drove back the chill of the snowfall. The shadows seemed to shrink from Yagi’s movements, retreating as though the dawn itself had risen.

Now, with his master’s words, he understood. That dance had been no mere celebration, but a ritual. It was the breath of the sun itself, carved into motion.

Izuku’s hand tightened over his knees, his heart swelling. One day, he swore he would master that dance.

Yagi’s voice cut through his memory. “Such power is difficult for the body, and few can wield it for long. You are the one who will carry this torch when I am gone.”

Yagi huffed a laugh. “That is why your training is so hard.” Then he sombered, shoulders falling. “I’m sorry I didn’t tell you what you were getting into sooner.”

Izuku’s breath caught in his throat, the enormity of it pressing down on his shoulders. But at the same time, deep within, that same fire stirred. Bright, unyielding. He wasn’t upset that Yagi had kept this from him, because this is the path that he had asked for. 

“And even if she is dead, I want to make sure nobody gets killed ever again!”

He had meant that with all his being. He wrestled every day with the fear that his mother was truly gone, but there was still life worth protecting. Izuku shook his head, heart thudding painfully as he gripped his master’s sleeve. “I’m not upset, but–” 

Izuku stared at him deeply. “–why do you continue to wear it?”

The firelight caught against the mask as Toshinori tilted his head, casting his carved features in strange, shifting shadows. His reply came softer, almost reluctant.

“It is best that I keep it on. You do not want to see what I look like beneath it.”

The words struck Izuku harder than he expected. There was no jest in his teacher’s voice, no booming laugh to soften the edges. Only something that surprised him– sorrow and shame. The boy’s chest tightened, and his curiosity only sharpened.

“That’s not true,” he said, his voice trembling but determined. “I do want to see. I don’t care what you look like, Master Yagi. You’ve taught me, protected me, believed in me… why would I turn away from you now?”

His master didn’t say anything, just turned to face away from him.

Slowly, carefully, he set his bowl down on the floor. “Please,” he said softly. “I want to see you.”

Yagi sighed heavily and shifted his body to face him, bangs billowing in the wind. He made no move to stop him. His silence was not agreement, but it was not refusal either. Izuku’s small hands trembled as they rose to the carved wood, bangs tickling his fingers as he gripped the mask gently, almost reverently. 

For a beat he rested them there, taking one last good look at the red and black etchings, then drew it away.

The man revealed beneath was nothing like the towering figure of strength the mask suggested. His cheeks were hollow, skin stretched tight over sharp bones. Deep scars ran like rivers across his jaw and throat, and his lips were drawn thin with pain long endured. It was the face of a skeleton.

And then there were his eyes.

For the first time, Izuku saw them, a piercing, electric blue, bright even through the shadows his brow cast. They seemed out of place in that ruined face, too alive, too unyielding, as if no amount of suffering could dull their light. For a long moment, Izuku could only stare, breath caught in his throat. Izuku felt tears prick at the corners of his own eyes, but not from fear. His chest ached with something heavier, sharper. Compassion. Admiration. Grief for all this man had endured.

“You…” Izuku’s voice came out as a  whisper when he tried to speak. “What happened to you?”

For a moment, Toshinori only held his gaze, the silence stretching heavy between them. Then he exhaled, long and weary, and clutched his knees.

“All for One,” he said at last, and the name itself seemed to sour the air. 

Izuku inhaled sharply, eyes wide with distraught as he looked at his master. All for One had done this?

Toshinori lifted a hand to his ribs, where the fabric of his haori hung loose over his hollow frame. “He nearly killed me. I was torn open, bones shattered, organs ruined. Every breath since then has been borrowed time.”

Izuku swallowed hard, his fingernails digging into the mask in his lap.

Toshinori’s voice continued bitterly. “Every master of Sun Breathing has fought him. I gave everything, and it was not enough. That failure has haunted me ever since. And now…,” his master’s voice broke with unshed tears. “I see history repeating itself.”

Izuku’s tears fell freely. “T-then I’ll change it.” His words trembled, but they rang with fierce, stubborn resolve. “I’ll end him. No matter what it takes.”

Yagi turned his head just enough to be bathed in shadow, but the tremor at the corner of his mouth exposed his true feelings. This throat bobbed hard, jaw working as if to force the sob back down. Izuku just watched him in shock.

Slowly, with hands that shook more than Izuku expected, Yagi reached down and snatched the mask from his hands. He settled the carved rabbit face over him again, and for a moment the hut seemed colder as the wall returned.

Izuku flinched, taken aback by the sudden dismissal, the mask a curtain drawn between them just as he’d opened a door. Toshinori’s fingers lingered at the knot, as if the act itself cost him something. He did not meet Izuku’s eyes until a few moments later, but all Izuku stared at was empty black paint.

“It’s getting late.”

This conversation is over, go to bed.

Disappointment settled in his stomach like a stone. For a moment, just a brief fragile heartbeat, he had seen his master as he truly was– not the aloof warrior, but a deeply hurt man. And then it was gone, hidden away behind carved wood and clipped words, as if Izuku had only imagined it.

Izuku didn’t say anything as he stood, he just bowed and walked to his cot. He laid down on his side, facing away from the man. His throat ached from holding back sobs, and he forced his eyes shut. He knew it was childish, punishing the man with the silent treatment, but right now Izuku couldn’t stop himself.

The boy didn’t sleep that night. Instead, all he felt was emptiness he hadn’t felt in a long time.

Sscratch- Sscratch- Sscratch- 

It was a few nights before Izuku would be sent off alone to enter the final stage of training. His bleary eyes caught his master's figure once again sitting by the open door through the dark. Steady hands worked a knife with care against wood.

Sscratch- Sscratch- Sscratch- 

Izuku’s eyes closed heavily from exhaustion.

When morning came, he couldn't remember if it had been real or a dream.

The path leading back to the hut was long and uneven, every step an effort. Izuku leaned heavily on a stick he found to use as a crutch, his legs trembling with exhaustion. His body bore the marks of the trial, cuts, bruises, the ache of near-death still fresh, but his gaze was steady, determined. He had passed the test, he had survived.

And he was so happy to go home and tell Yagi the good news.

Their parting had been one filled with pinched, shaky tones and unshed tears. It was bittersweet, the moment when he received a mask achingly familiar to his master’s, made by Yagi’s own hands. It was also in the likeness of a rabbit, except the eyes were painted wide with freckles like stars painted in golden yellow.

“I have carved this mask for you with a protection ward. I hope it brings you luck during the trial.”

In a way, it seems it had. It had stopped a deadly blow to the head where it rested, giving him an opening to plunge his sword into the gut of a large demon, ending their life and saving his. As much as he cherished the gift and wanted to keep the beautiful art piece safe, all he had left were the shattered pieces in his side pouch.

Maybe Yagi could make him another one.

As he reached the clearing, the door to the hut flew open. Toshinori came rushing out, haori flaring behind him, the rabbit mask pulled up and resting on the crown of his head. His gaunt face was unguarded, electric-blue eyes wide with fear and disbelief all at once.

“Izuku!”

Before the boy could take another step, Toshinori closed the distance and seized him in a fierce embrace. The sudden strength of it knocked the stick from Izuku’s grip, and he sagged into the man’s arms, breath hitching. His arms held Izuku as though he were the most precious thing in the world.

“My boy,” Toshinori whispered, voice breaking with unrestrained relief. “You’re alive.”

The words sank deep, warm and undeniable, and Izuku felt his chest swell until tears blurred his vision. Toshinori drew back just enough to grip Izuku’s shoulders, scanning his battered form, then pulled him into another crushing hug, his laughter and sobs tangled together. Izuku buried his face against the fabric of his master’s haori, trembling from exhaustion and happiness alike. “You did it,” he choked out, blue eyes shining with pure happiness and pride. 

“I’m so proud of you.”

The years passed like the slow grind of stone against stone.

When Izuku received his sword, the time came for Izuku and Toshinori to part ways once again. There was no argument, no great scene, only an understanding that each had their own battles to fight. Toshinori’s path bent toward shadowed trails, following whispers of All for One’s movements, prying loose secrets from half-ruined shrines and dying tongues. His body, already frail, grew thinner still; the once-towering figure seemed eaten alive by the years, yet his eyes still burned with stubborn blue fire.

Izuku’s road was no gentler. He became a full-fledged demon slayer, the weight of the black blade he carried heavy with the weight of duty. Missions carried him from village to village, always guided by the caw of his kasugai crow, always driven by the memory of his mother's body hanging by her neck. Blood became his constant companion, but still he pressed forward, chasing the hope that one day he would find her.

It was late when he finally made it to the next town, his next mission.

The village bustled with life, lanterns burning warm against the creeping dusk. Laughter and haggling spilled from stalls, the clatter of cups from taverns. To the people, it was an ordinary night. But Izuku knew better. Beneath the surface, fear lingered. He had seen it in the way mothers clutched their children a little tighter, in the empty spaces between shops where no one dared to linger, in the whispers of travelers who spoke of vanishings that went unsolved.

He was here to root it out.

The thought of All for One’s lesser demons lurking in the shadows made his stomach knot. They were not like the demons he had fought before, feral and single-minded. These ones had power, cunning, and purpose. If he could strike one down, it would bring him one step closer to finding the location of All for One, and his mother. One step closer to her voice, her touch. Whether as a human or… something else. He clenched his fist tight, willing the thought away before it could eat at him.

He had left Shouto, another Mizunoto, behind to finish their previous mission, a demon nest that still needed cleaning. His friend’s quiet nod had been enough to assure him things would be handled. That trust freed Izuku to chase the more dangerous trail, the one that led him here, alone. 

At least, he thought he was alone.

A figure came into view from the opposite side of the street, familiar and unmistakable.

The figure gripped his mask, pushing it up onto his head, the carved rabbit face tilted back to reveal a set of surprised blue eyes as if he too couldn’t believe what he was seeing.

Izuku’s breath caught. For months, he had dreamed of this meeting, wondering if his master still lived, if the next whisper of All for One’s movements would end with news of his death. Yet here he was, standing before him as though pulled from memory.

Izuku moved before he even realized it. He forced his stride into something steady, something measured, nothing that would draw eyes in the bustling street. But the moment he drew close, all restraint shattered. His arms folded tight around the man’s frail frame, clutching him with all the strength of months of silence and fear.

“Toshinori” Izuku’s voice broke against his chest, quiet enough not to draw attention, but fierce with relief.

Toshinori staggered a step at the sudden force, then his arms closed around Izuku just as tightly, a rough exhale shuddering out of him. His mask slipped further back on his head, forgotten, as he pressed his chin against the boy’s hair.

“My boy,” he whispered hoarsely, voice trembling with happiness.

Izuku swallowed hard, pulling back just enough to see his face, his own eyes shining in the lamplight. “I thought… I thought I’d never see you again.”

Toshinori’s lips curved into a faint, tired smile, his blue eyes still glistening. “And yet here you are. Stronger than before.”

Izuku’s fingers tightened against the man’s sleeve, unwilling to let go. His voice dropped, urgent and low, almost afraid that if he spoke too loud this fragile moment would vanish. “What are you doing here, Master?”

Toshinori glanced around, the lines of his face tightening as he caught the curious looks from passersby. Without a word, he steered Izuku gently toward the side of the street where the noise of the market dimmed.

“I heard whispers,” Toshinori said, his voice low, serious. “Information that one of All for One’s favored demons was moving here.” His blue eyes flicked down to Izuku. “Why are you here?”

Izuku straightened, his expression still surprised. “I’m here on assignment. My crow delivered the same lead to me.” He let out a humorless laugh, rubbing at his arm. “So I guess…I’m here for the same reason you are.”

For a moment, silence hung between them, heavy with unspoken relief that fate had allowed them to cross paths again. Then Toshinori’s lips curved into a fond smile, a spark that he was still the same person Izuku knew.

“Well,” he said, clapping a scarred hand against Izuku’s shoulder, “I suppose this is good fortune then. It seems we won’t be walking into danger alone. That is, if you don’t mind teaming up with an old man like me,” his voice tried for levity.

Izuku shook his head sharply, green eyes blazing with earnest fire. “You’re not old!” The words came out defiant, as if he could banish the frailty clinging to Toshinori simply by refusing to acknowledge it.

Toshinori chuckled softly, the sound rough but genuine. “If only that were true.” His gaze softened as he studied him, pride mingling with sorrow. “But you, my boy, look at you! You’ve grown,” Yagi remarked, resting his hand on Izuku’s head before pulling it towards his chest to compare from memory.

Toshinori gave a soft hum of thought, gaze flicking toward the glow of lanterns deeper in the village. “This won’t be quick,” he murmured, his voice dropping lower, meant only for Izuku. “If these demons truly serve All for One, they won’t want to be caught. They’ll hide, wait, watch. But… creatures like that grow arrogant. Sooner or later, they’ll make a move.”

Izuku nodded, his jaw set tight. “Then we’ll be ready.”

“All the more reason we shouldn’t meet the night unprepared. Come.” He gestured toward the inn district, where the smell of cooked rice and warm broth drifted out into the street. “Let’s find a place to stay so we can rest. And, it will be easier to plan once we’re not standing in the open like sitting ducks.”

Toshinori had purchased a room at a local inn for the two of them, and Izuku felt increasingly grateful at not having to sleep in the dirt again as well as the warm meal he ate that night.

The village, however, slept uneasily under the shroud of night. Lanterns guttered in the wind, their glow bending shadows across the dirt road. He walked at his master’s side, hand resting on the hilt of his blade, every sense on edge.

Then it came. A ripple in the air. A stench of blood that made his stomach twist.

“Master,” Izuku said, stopping short.

Toshinori nodded grimly. “I smell it.” His hand slid his mask down, the rabbit face staring forward as he lifted his sword. The faint rasp of his breath carried louder in the quiet, but his eyes blazed sharp, searching the darkness.

From the roof above, a figure dropped like liquid shadow. A pale grin split its face, too wide, too jagged, eyes burning crimson in the dark. And behind it, a second presence crept forward from the alley, slender and sharp, its limbs stretched impossibly long.

“Ah, if it isn’t two slayers from the sun breathing school,” the first demon crooned, its voice scraping like glass. “How interesting.”

The other licked his lips, tone full of hunger. “I love rabbit flesh.”

Izuku’s pulse thundered. There was more than one of them, the two demons radiating killing intent strong enough to smother the street.

“Stay calm,” Toshinori ordered, though his tone was strained.

The demons struck at once. The long-limbed one lashed out, its arm whipping through the air like a spear. Izuku’s sword flashed– CLANG! Sparks leapt as he caught the blow, the force rattling his bones. He gritted his teeth, sliding his stance into sun breathing, exhaling slowly. His blade swept in a radiant arc, light spilling like fire across the night as he cleaved through the demon’s reaching limb. Black blood hissed where it splattered, sizzling against the dirt.

The second demon was already there, bearing down on Toshinori to his right.

Toshinori gripped his golden blade, sun breathing flaring through his weakened body, a brilliance of heat and power bursting from his sword. For a heartbeat, he was the warrior Izuku remembered, his strikes burning golden light across the cobblestones. The demon shrieked as its flesh seared, retreating under the radiant assault.

But the price was immediate from playing offense. Toshinori staggered, coughing blood, his body faltering under the weight of his own technique.

“Master!” Izuku tore free from the other demon, shoving himself into the fray. He clashed with the snarling, grinning one, steel screaming against claws.

The long-limbed demon lunged for Toshinori’s exposed side.

Izuku pivoted, every ounce of his body burning with resolve. He cried out his attack as his blade burst forward, a blazing thrust like a spear of dawn. It pierced clean through the demon’s chest, the light tearing it apart from within. The monster’s scream split the night before dissolving into ash.

But in that opening, the second demon’s claws ripped across Izuku’s side. Pain exploded white-hot and he gasped, stumbling, but forced his blade through one final arc, catching the demon at the neck.

The head fell, rolling to the floor. The body burned away till it was ash.

Izuku’s legs gave out beneath him. His sword clattered to the dirt as blood seeped between his fingers, his breaths coming in ragged gasps.

“Damn it,” he muttered, the world tilting. “Not… yet…”

The last thing Izuku felt before darkness claimed him was the warmth of living hands as they caught his dying body just before he hit the ground. 

The first thing Izuku registered was the blinding morning light. 

Thin rays filtered through the paper window, scattering across the floorboards in pale orange hues. He blinked groggily, lids heavy, every inch of his body dragging with exhaustion. He didn’t panic immediately because of the daylight’s safety, but then came the pain. A sharp, searing throb tore through his side, making him bite down on his teeth to stop himself from crying out. On his other side he felt a soft warmth curled against him. Izuku turned his head, slowly, carefully.

His master lay beside him, his breathing deep and even as he slept. His gaunt frame curled just close enough that one arm wrapped around Izuku, holding him as though to shield him. Toshinori wasn’t under the blankets of his futon because gripped tightly in his other hand, was his sword to guard them, ready to attack at the first sign of danger.

For a moment, Izuku simply watched him doze, too stunned to speak, too weak to move.  Closing his eyes, Izuku let himself pretend. He pretended he was back in his childhood home, and that the distant sounds of the inn was his mother in the kitchen preparing breakfast while Toshinori slept peacefully beside him. 

His perfect family.

Izuku shifted himself further into the warmth of that protective hold, the ache in his side protesting at the movement, but he ignored it. The familiar scent of pine clung to his master’s haori, worn from years of use. 

The slight movement was enough.

“Izu–ku?” Toshinori whispered, his voice rough with sleep.

His master stirred, a faint groan catching in his throat as his brows furrowed. His grip on the sword tightened reflexively before his tired blue eyes cracked open. He squinted at the boy in his arms, disoriented at first, until realization dawned on him.

“Sorry, Master,” Izuku murmured, groggy green eyes meeting surprised blue. “I didn’t mean to wake you.”

Toshinori blinked a few times, as though uncertain if what he was seeing was real. Then his expression softened into a smile Izuku had only gotten a glimpse of once before, when he returned alive from the trial. The arm that lay draped around him shifted, pulling the blanket until it covered them both, as if Izuku weren’t already close enough.

“Don’t apologize,” he replied with soft assurance. “My prayers were answered– that when I woke, you would still be alive.” Toshinori’s eyes glistened faintly in the morning light, his voice tight with raw emotion. “You scared me half to death.”

Izuku’s breath hitched as he looked the man in the eye. Gone were the walls that had loomed so high between them when they had first met, and even the distance that lingered. In their place was something raw and unguarded, a current of emotion conveyed through his relieved gaze. For the second time, Izuku felt he was not just a student being shielded by a teacher’s duty, but a boy seen, held, and cherished.

His arms tightened around Toshinori despite the stab of pain in his side. “I thought I lost you too,” he whispered into his chest.

Toshinori exhaled slowly, the sound weary. At last, the sword slipped from his hand, clattering softly to the floorboards. Freed, that arm wrapped around Izuku and drew him closer still, as if by holding him tighter he could anchor the boy to this world.

“Not yet,” Toshinori said fiercely. “Not yet…”

They laid like that for a while, Izuku finding himself drifting back to sleep. He was so tired, he didn’t want to move for at least a few years, remaining forever curled up, warm and safe. But to his distress, a hand brushing once more over Izuku’s hair roused him from his slumber. Hazy green eyes met those of his master, who was looking down at him worriedly. “You should eat. You’ll need strength if we plan to get you to the mansion alive so you can recover fully.”

Izuku blinked blearily, following his movements with half-lidded eyes as he propped pillows against the wall behind him for Izuku to sit against. His master moved stiffly, each shift betraying the lingering toll of the battle. Yet even with the sunlight catching the deep lines of fatigue in his face, Toshinori’s focus was fixed only on him.

Carefully, his master helped Izuku sit upright. He struggled greatly, trying to push himself, but his hands fumbled weakly against the bedding. Pain lanced through his side, forcing a sharp hiss from his lips, but still he fought to rise. “Easy,” Toshinori murmured, catching him with gentle but firm hands. Then when Izuku’s heavy breathing settled, he picked up the bowl, stirred it once with the spoon, and lifted a small portion toward him.

Izuku hesitated. It felt childish somehow, being fed like this, but his master’s expression left no room for argument. He opened his mouth quietly, letting the warmth of the porridge spread through him. Toshinori fed him in silence, careful and steady, as though the smallest mistake might hurt him. 

Soon his awareness began to return, pulling him up from the fog that had wrapped around him since he first awoke. The porridge no longer dulled the pain; instead, it made space for his thoughts to stir again, and with that clarity came the weight. He had been too overwhelmed, letting fear control his weakness that he never got to ask the demons about All for One or his mother. Instead he only caused trouble for his master, and now they were no closer to finding All for One’s hiding place. All that work that Yagi had done was now rendered useless, the trail had disappeared with the demons he had killed. Izuku’s eyes began to sting. He swallowed hard, but the ache in his throat didn’t leave.

“I’m sorry,” he said, voice breaking through the quiet.

Toshinori sighed. “What did I say about apologizing?” 

Izuku shook his head, tears welling despite his effort to blink them away. “No, you don’t understand–” His voice cracked. “I ruined everything. I was too weak, and I couldn’t even get any information. I couldn’t ask about her. I tried, but then I just–” He gestured weakly to his bandaged side, breath hitching. Izuku squeezed his eyes shut, fists curling tight in the sheets. “I failed her, Master, I keep failing her.”

Toshinori set the bowl down quietly and reached for him, steadying Izuku’s trembling hand in both of his own. His palms were calloused, his grip firm but full of care.

“You did not fail, you lived. And because you lived, there will be another chance. All for One is still out there, so there is always hope for an answer. You must understand that to be in the demon slayer corp, being a demon slayer comes first. Your safety comes first.”

“But–”

“No buts,” Toshinori interrupted sternly. “You must understand this, Izuku. You are my successor. If you die, the hope that Sun Breathing gives to this world dies with you. Everyone is counting on you, everyone who depends on the demon slayer corps depends on you surviving.”

The words hung between them, fragile and heavy, and Izuku knew his master was right. Toshinori brushed his hand over Izuku’s hair, pushing his bangs back, the motion almost reverent. “You’re mine to protect, y’know,” Toshinori said, his tone unwavering. 

“I chose you. Not because you were the strongest, or the fastest, or the most talented. I chose you because you never gave up. Because you kept standing even when the world kicked you down. That kind of heart…” The fierceness in his master’s gaze, the warmth of his hand over his hair, pressed against him like sunlight cutting through the window made his master’s hair glow golden.

“That kind of heart is worth protecting.”

Izuku’s chest shook, and the tears he had been holding back spilled freely, hot and unrelenting. His sobs hitched as he pressed his face against Toshinori’s chest, overwhelmed by the brutality of the fight, the fear, the hope, and the lingering pain in his side.

He wanted to say it, to tell him, You’re like a father to me, but those words, Izuku found, he never could utter. His body was spent, his mind dulled by exhaustion, and the blood loss made every thought feel fuzzy. Right now, he didn’t have the strength to untangle all his feelings. So he let himself cry, let himself grip his master’s golden yellow haori, let himself feel the warmth and safety without having to explain it. I’ll tell him someday… he thought.

After Izuku began to quiet into sniffles, an exasperated smile tugged at Yagi’s lips. “You little crybaby,” he murmured, brushing the tears from Izuku’s cheeks with calloused fingers. Izuku hiccuped, trying to compose himself, but before he could pull away, Toshinori pressed his hand against Izuku’s forehead. “Hmm… you’re a little warm.”

Carefully, Toshinori scooped his arms underneath Izuku, adjusting the boy so that he was laid back down against the bedding. “Come on,” he said gently, “back to bed you get.”

Izuku murmured, half-heartedly protesting, but his voice was weak, dulled by exhaustion and tears. Toshinori chuckled softly, shaking his head as he brushed a damp green curl from Izuku’s forehead. “Shh, my prince of nonsense.”

He tucked him in tightly and carefully, setting the blanket over Izuku’s shoulders and chest, cocooning him like soil over a fragile seedling. Toshinori’s hand lingered on the boy’s chest for a moment longer, feeling the faint rise and fall of his breaths, grounding him, letting him know he was guarded. Izuku’s eyelids fluttered once, then settled, and his breathing evened out, signaling the call of sleep.

In a sudden, unthinking gesture, Toshinori leaned down and pressed a gentle kiss to Izuku’s forehead. “Sweet dreams, my boy,” he whispered, the words barely audible.

He stayed there for a long moment, watching over him, listening to the slow rhythm of his breaths, the faint warmth radiating from his small frame telling the world I’m alive. For now, the battle was done, the demons were defeated, and the boy he had come to love like a son was safe. Toshinori allowed himself the briefest moment of respite, getting up to make himself some calming green tea, then sat back down to his attentive watch.

Tomorrow, the fight would continue. All for One was still out there. But for today, in this quiet inn room, in the unspoken bond between them, there was peace. A fragile, fleeting, perfect peace.