Archive of Our Own ^beta

Chapter Text

The river had never felt so cold.

Thirteen-year-old Giyuu Tomioka stumbled barefoot along the mountain stream, his blood diluted by the rushing water as it curled around his knees. His steps were clumsy, uncertain, his eyes fixed on nothing and everything at once. He could still hear Tsutako’s voice, soft like rain. Her scream when the demon had lunged. The sickening crunch of bones breaking.

He had run.

He didn’t remember when he stopped running, or how many days had passed. He didn’t care.

His body, once strong from practice sessions with wooden swords and self-taught kata in the woods, was now a trembling frame hollowed by grief. His breath hitched as the forest blurred, and his legs finally gave out.

Giyuu collapsed.

And somewhere far away—past the thrum of panic, past the ache in his ribs and the cold creeping into his bones—he thought he heard the whisper of wings.

⸻

When Giyuu next opened his eyes, he thought he had died.

The room was pale and soft. The air smelled faintly of wisteria and herbal salve. Something cool was pressed to his forehead, and there was warmth at his side—hands, carefully tending a wound. A woman was humming. Not Tsutako.

“Ah, you’re awake,” said a voice. Giyuu blinked up at a face unfamiliar to him—gentle, elegant, and framed by black hair. The woman’s lavender eyes softened with relief. “You poor thing. You must’ve been out for days.”

“…Where…?”

“This is the Butterfly Estate,” she said. “My name is Kanae Kocho.”

He tried to sit up, but a small hand pressed against his chest.

“Lie down,” said another voice, sharper, younger. “You’ve been poisoned. The demon’s claws were coated in something nasty. You’re lucky we found you.”

Another girl. Much younger, with piercing violet eyes like a blade sheathed in petals.

“I’m Shinobu. Kanae’s younger sister. You can thank us later.”

“S-Shinobu,” Kanae chided gently. “Let him breathe.”

Giyuu’s lips parted. He meant to say thank you. He meant to say nothing at all.

But what came out instead was: “Tsutako… my sister…”

And then he cried.

⸻

The Butterfly Estate, he quickly learned, was more than a place of healing. It was alive in a way the rest of the world wasn’t.

Kanae Kocho was like a second sun—warm, patient, always smiling, even when she carried more sorrow than she let on. Shinobu, by contrast, was a whipcrack of energy, sharp and exacting. She didn’t coddle him. She didn’t let him drift in silence the way the other healers did. She challenged him.

“You’re not the only one who’s lost someone, Giyuu,” she said, one evening, after he had refused dinner again. “But if you keep acting like this, your sister’s sacrifice will mean nothing.”

He threw the tray against the wall.

He hated her.

Then he cried again, and she sat next to him in the wreckage without a word, handing him a fresh cup of tea.

⸻

Time passed strangely in the garden.

Kanae would read to him. Shinobu would force him to learn herbs. Kanao, a little girl barely older than a child’s doll, watched from the edge of every room in silence. She didn’t speak, but she followed Giyuu like a shadow.

He didn’t mind. He liked shadows. They never asked questions.

He learned to walk again. To breathe without pain. To hold a bokken. He had never had formal training—just books, instinct, and the stubbornness to keep going. At first, it was Kanae who guided him, her movements as fluid as petals in the wind. She practiced Flower Breathing, a style so unlike the strong, direct strikes he had taught himself. It was poetic. Flowing. At first, it made no sense to him.

“Breathing is not just about power,” Kanae said. “It’s about grace. Precision. Kindness.”

Kindness. That was something new.

⸻

He trained with Shinobu, too.

She wasn’t like Kanae. Where her sister moved like wind in spring, Shinobu was summer lightning—unforgiving, focused, and faster than the eye could track.

“You’re stiff,” she said. “You’re thinking like a rock. Try thinking like a stream.”

“I’m not good at that,” he muttered.

“Then get better.”

He did.

It took months before his body caught up to his soul. But eventually, the boy who had run into the mountains and collapsed under his grief… stood tall again. Quieter, yes, but not silent. He spoke when it mattered. He asked about Kanao. He argued with Shinobu—sparring became a regular event. He meditated with Kanae.

And he never forgot what he had lost.

⸻

One night, as cicadas chirped beneath a waning moon, Giyuu walked into the garden to find Kanae kneeling at the koi pond, her face lit only by starlight.

“You’re restless,” she said, without turning.

“You always know,” he said, sitting beside her.

“I know you,” Kanae replied.

He hesitated. “Why did you take me in?”

She smiled. “Because you were drowning. And no one deserves to drown alone.”

“…I want to join the Demon Slayer Corps.”

“I know.”

Silence bloomed between them, peaceful.

“I don’t want anyone else to lose their family.”

“I know that too.”

⸻

He passed Final Selection at fourteen.
He killed his first demon in two strokes.
He mastered Water Breathing by fifteen, after recovering ancient scrolls and teaching himself the forms.
But it never felt whole.
So he added the grace of Flower Breathing. He made it his own.

Shinobu called it “Water Bloom,” half in jest, half in awe.

By sixteen, he was known throughout the Corps as the “Petal Current Swordsman.” His movements were fluid, like flowing ink. His strikes were merciful—elegant even in death.

People liked him. Even Tengen. Even Obanai.

Only one person didn’t.

⸻

“Tomioka,” spat the Wind Hashira. “You’re late.”

Giyuu glanced at the silver-haired man waiting by the cliffside. Their mission was a joint one—unusual, but not unheard of. Two Hashira, one Upper Moon. Remote region. High risk.

“You’re early,” Giyuu replied, calm as ever.

Sanemi Shinazugawa narrowed his eyes. “Don’t get smart with me, Prettyboy. I’ve read your reports. Flowery bullshit. You don’t even kill demons, you put them to sleep.”

“It’s more effective than screaming at them.”

Sanemi growled.

Giyuu smiled. “Nice to meet you too, Shinazugawa.”

Chapter Text

The first time Kanao spoke to him, it was barely more than a whisper.

They had just finished evening training in the garden. Giyuu had been showing her a water-based kata—one of the softer ones, adapted to ease her footwork into the natural rhythm of the river. She was a fast learner, but she always hesitated before each motion, like she was waiting for someone else to pull the string.

As they sat beside the koi pond, catching their breath, she surprised him.

“Why… water?”

He blinked. The sky was violet with dusk. Cicadas chirped in the distance.

“…Because I was drowning,” he said. “And it saved me.”

Kanao nodded once, then gently lowered her coin back into her pocket. It hadn’t been flipped.

From that day on, she began to speak—just to him. And Giyuu felt something small and warm settle into his chest.

⸻

He grew quickly after that.

By fifteen, he had honed his own variation of Water Breathing. It was still grounded in the traditional forms—Flowing Dance, Constant Flux—but there was a new elegance threaded between each strike. He wove in Flower Breathing’s grace, turning hard lines into smooth arcs. Water no longer just surged or sliced—it bloomed.

Shinobu dubbed it “Water Bloom.” Giyuu thought it sounded a little ridiculous.

But Kanae had smiled, her eyes crinkling. “No, it suits you.”

⸻

Then came the mission that changed everything.

The report had been simple: a demon was haunting a rural town several hours northeast. Multiple disappearances. Witnesses spoke of sweet perfume just before vanishing.

Kanae had gone alone.

When the crow delivered the message that she’d been gravely injured, Shinobu broke a plate in her hand and didn’t even notice the blood. Kanao ran, silent as ever, to pack the medical supplies. Giyuu was already grabbing his sword.

They reached her in time—but just barely.

Kanae lay crumpled beneath the sakura trees, her haori torn and her eyes full of peace she hadn’t yet earned.

“Ah… Giyuu… you got taller…”

He fell to his knees beside her, his voice cracking. “Don’t speak. Shinobu will—she’ll fix this—”

“I’m glad… I met you,” she whispered. “Both of you…”

Her hand was warm when she placed it in his.

“I saw your water bloom,” Kanae said. “It was beautiful…”

Then she closed her eyes.

⸻

The days after Kanae’s death were heavy with silence.

Kanao didn’t speak at all. Shinobu didn’t stop speaking—except none of her words were kind. Every sentence was a needle. Every smile was stitched on with spite. The entire Estate became hushed, like the air itself was mourning.

Giyuu didn’t cry. Not this time.

Instead, he trained.

He trained until his hands bled, until the garden paths were soaked with sweat and the water in his gourd ran dry. Kanao watched him from the porch, hugging her knees. She never said anything, but he felt her eyes on his back every morning.

“I’ll protect what she left us,” he said one evening, when he found Shinobu alone in the infirmary, grinding herbs with unnecessary force.

She didn’t look up. “You can’t protect everything, Giyuu.”

“No,” he agreed. “But I’ll protect her. And you.”

“…Idiot,” she muttered, blinking quickly.

He smiled, for the first time in days.

⸻

At Fifteen, he became the Water Hashira.

The others were curious about the boy from the Butterfly Estate. Rengoku welcomed him with a hand on his shoulder and a bright laugh. Mitsuri told him his sword forms looked like dancing. Obanai pretended to dislike him, but always ended up standing next to him at meetings. Even Gyomei respected his discipline.

Giyuu wasn’t loud, but he wasn’t silent. He spoke clearly, with purpose. He joked, sometimes dryly. He always carried the smell of wisteria and a freshwater lake on his robes.

Only one Pillar clashed with him like oil in a river.

⸻

“You’re too soft,” Sanemi growled as they tore through the mountain pass, demon blood splattered across both their uniforms. “You don’t even aim to kill—what the hell kind of swordsman are you?”

Giyuu flicked blood from his blade. “The effective kind.”

They had just fought off three demons at once—two of them working in tandem. Giyuu had incapacitated both within ten strikes, forcing them down with elegant sweeps that disoriented and disabled. Sanemi had simply torn through the third like a storm.

“You left the kill to me,” Sanemi snapped. “Why? Too pretty to get dirty?”

Giyuu wiped his blade clean. “No. I wanted to see how loud you’d get when you’re annoyed.”

Sanemi froze.

“…You’re messing with me now?”

Giyuu turned to him with a smile that was just a bit too calm. “Would you prefer I ignore you like everyone else?”

Something flickered in Sanemi’s eyes—confusion? Shock?

Then he scoffed and turned away. “You talk too much.”

⸻

They were sent on another joint mission the following week.

“Is the Master trying to kill me?” Sanemi muttered as they trudged through yet another forest, the scent of rot and blood in the air.

“Possibly,” Giyuu said. “I think he believes we’ll bond through mutual trauma.”

“You think this is funny?”

“A little.”

They were ambushed at nightfall—two demons again, one with a blood demon art that caused hallucinations.

Giyuu took the hit for Sanemi.

He barely had time to deflect the claw before pain flared through his ribs and the world twisted. He saw Kanae’s smile. Tsutako’s final breath. The garden in spring, red with blood.

He heard screaming. Not his.

Sanemi cut down the demon in a rage so brutal it left the trees shaking.

Then he turned and saw Giyuu, collapsed at the base of a tree, pale and still.

“Don’t you dare—don’t you dare die on me, Prettyboy—!”

Giyuu opened one eye. “You’re loud.”

“…You’re alive?”

“Unfortunately.”

Sanemi sank to the ground beside him, breath ragged. “Next time, let me take the hit, moron.”

“You’d have gotten angrier,” Giyuu whispered, “and made more noise. The demons would’ve known.”

“…You’re insane.”

“And you’re bleeding.”

Sanemi glanced down. He hadn’t even noticed the gash in his arm.

“Tch. Whatever.”

Giyuu leaned his head back against the tree and sighed.

“…Thanks for the yelling,” he said. “It helped me wake up.”

⸻

They returned to the Butterfly Estate together. Shinobu stitched Giyuu up in silence, her hands trembling slightly when she saw the bruises on his ribs.

“You’re reckless,” she scolded.

“He’s alive,” Sanemi snapped from the doorway. “Be grateful.”

She narrowed her eyes. “I am. I just don’t appreciate having to scrub demon poison out of his wounds while he flirts with loud-mouthed idiots.”

Sanemi sputtered. “Flirts?!”

Giyuu, half-conscious, smiled.

“…She’s somewhat not wrong.”

Chapter Text

“Swing again. You’re pulling to the right.”

Kanao’s brow furrowed, but she adjusted her grip and moved into stance.

They were training on the Butterfly Estate’s stone walkway, the afternoon sun filtering through wisteria vines. Giyuu watched her carefully—her breathing was steady, her footwork light, but she had hesitated again before transitioning from Flowing Dance to Petal Surge.

“You’re thinking too hard,” he said. “Let the movement carry itself. You don’t need to force the rhythm.”

“I don’t want to mess it up.”

“You won’t. Just stop trying to copy me.”

She blinked. “But you said—”

“Learn from me. Don’t be me.”

A pause. Then her shoulders eased.

She tried again. This time, the blade cut air like silk, a water-flower hybrid strike that made the hairs on Giyuu’s arm rise.

He smiled.

“Better.”

Shinobu passed behind them with a tray of medicine bottles. “Wow. Compliments from Giyuu. Is it spring already?”

Kanao smiled faintly. Giyuu raised an eyebrow.

Shinobu only winked. “Don’t let it get to your head, Kanao. He still thinks about sword forms in his sleep.”

“Do not.”

“You said Constant Flux in your dreams last week.”

Kanao giggled. Giyuu turned back to her with narrowed eyes.

“Again,” he muttered. “And don’t mess it up just because she’s watching.”

“Yes, Sensei.”

That evening, as Kanao studied scrolls in the garden and Shinobu tended to a fevered patient inside, Giyuu sat on the veranda, polishing his blade. The sun had just dipped below the trees, painting the estate in golden hues.

A crow landed beside him.

“MESSAGE! MESSAGE FOR TOMIOKA GIYUU! URGENT MISSION!”

He took the paper and skimmed it.

“Joint assignment,” he muttered.

Shinobu poked her head out. “Who’s the unlucky soul?”

“…Sanemi.”

She burst into laughter.

⸻

The mission took them west, where travelers had been disappearing along a cliffside path. Locals spoke of howling winds and shadows in the mist.

Giyuu didn’t mind the cold, or the quiet. He minded Sanemi’s pacing.

“You’re going to dig a hole into the stone,” he said.

Sanemi shot him a glare. “You’re too relaxed.”

“Maybe you’re too tense.”

“I’m prepared.”

“You’re vibrating.”

They argued like this every time, Giyuu calmly pointing out Sanemi’s temper while Sanemi snarled back insults that never quite hit the mark. They worked together too well to actually hate each other.

The demons came at night. Two again, and smarter this time.

Giyuu used water to drive one toward the cliff’s edge, where Sanemi intercepted with a vertical slash that split the thing in two. The second demon tried to flee, but a quick form from Giyuu’s Water Bloom locked it in place like a swirling net of petals and current. Sanemi finished it without a word.

Afterward, they sat near the cliff’s edge, blood drying on their uniforms, and let the mist soak their sleeves.

“…You didn’t hesitate,” Sanemi said.

“I never do.”

“No. I mean, when I was surrounded. You didn’t wait.”

Giyuu glanced at him. “I trust you to handle your end. I worry more about your mouth than your blade.”

Sanemi let out a sharp exhale—was that a laugh?

“…You’re lucky you’re pretty,” he muttered.

Giyuu turned his head, slowly. “What?”

“Nothing.”

“You just said—”

“I said NOTHING.”

“…Right.”

It became a pattern.

Giyuu and Sanemi, joint missions. Their fighting styles clashed—grace versus fury—but always synced in the end. And slowly, without meaning to, they found a rhythm.

Sanemi stopped questioning Giyuu’s softness. Giyuu stopped pretending Sanemi’s anger didn’t come from somewhere deeper.

Their arguments became banter. Their banter became familiarity.

And one evening, as they walked back toward the Estate through a field of swaying grass, Sanemi suddenly said, “You ever wonder if we’re gonna die without knowing if we made a damn difference?”

Giyuu was quiet for a beat. Then, “I think… if Kanao lives a long life, I’ll have made one.”

Sanemi didn’t respond right away.

Then he said, “Yeah. That’d be enough.”

They didn’t speak for the rest of the walk, but they didn’t need to.

⸻

Kanao grew sharper by the week.

She had Giyuu’s discipline, Shinobu’s precision, and Kanae’s grace. But she was becoming something all her own. Giyuu watched her move through sparring drills like a dancer—fluid, reactive, intuitive.

“You’re hiding techniques from me,” he told her one afternoon after she caught him off guard with a twist he hadn’t taught.

She looked at him innocently. “Am I?”

“You are.”

She tilted her head. “Maybe I wanted to see if you were still paying attention.”

He smirked. “I never stop.”

Later that day, Shinobu pulled him aside.

“She’s almost ready,” she said.

“I know.”

“You’ve made her strong. But she follows your example in other ways too.”

“…How so?”

“She’s getting reckless.”

He sighed. “We all are. It’s a reckless world.”

Shinobu didn’t argue. But her eyes lingered on his bruised wrist, still healing from the last mission.

“She worries about you,” she said. “Don’t make her lose another sibling.”

That night, Giyuu found Kanao watching the koi pond again.

“I’m not going anywhere,” he told her gently. “You know that, right?”

She didn’t answer. But she reached into her pocket and held out the coin.

“…I don’t need it anymore,” she said. “But… I think you should have it.”

Giyuu took it, folding her fingers around his hand.

“I’ll keep it,” he said, “in case I ever forget what I’m fighting for.”

⸻

Sanemi showed up uninvited a week later.

“I heard your tsuguko knocked you on your ass,” he said, leaning against the gate with a smirk.

“She caught me off guard.”

“I thought you never let your guard down.”

“Maybe I trust her.”

Sanemi tilted his head. “You trust a lot of people. Including me. Why?”

Giyuu didn’t blink. “Because you keep coming back.”

“…Dumb reason.”

“It’s mine.”

They stared at each other for a long moment.

Then Sanemi sighed and looked away. “Tch. You’re exhausting.”

“Would you rather someone who doesn’t talk to you at all?”

“…No.”

“…Good.”

They sat under the wisteria trees that night, Sanemi grumbling about Shinobu’s tea being too flowery, and Giyuu pretending not to notice how often their shoulders brushed.

Neither of them moved away.

Chapter Text

Kanao’s first solo mission came on a late summer morning.

A crow arrived bearing the details: a suspected demon near the Yuzuhira mountains. Small village. One confirmed death. Potential threat rising.

Giyuu stood with her at the gate of the Butterfly Estate, the morning sun bright over the trees. She adjusted her scabbard, her eyes calm.

“I’ll be back before dusk,” she said.

“You don’t need to rush.”

“I want to.”

He gave her a small nod. “Trust your instincts.”

She hesitated—then stepped forward and hugged him, arms quick but certain around his waist.

“I’ll make you proud,” she said into his haori.

“You already have.”

Shinobu watched from the balcony, a quiet smile playing at her lips. When Kanao was gone, she came down beside him.

“She’s grown,” Shinobu murmured.

“We all have.”

“…Even you.”

Giyuu raised an eyebrow. “That was almost a compliment.”

“I’m losing my touch.”

He smirked. “No, just your bitterness.”

She laughed softly. “I can’t help it. You’re not the boy who wandered into our garden anymore.”

“No. But he’s still here, somewhere.”

She looked at him sideways. “Is that why you keep training so hard?”

Giyuu didn’t answer right away.

Then: “It’s because I know it can all be gone tomorrow. So I want to make every piece of it count.”

Shinobu looked away, expression clouded with memory.

“…Kanae would’ve said the same.”

He didn’t say anything. He just watched the trees sway—peaceful for now.

⸻

Sanemi arrived mid-afternoon, covered in dirt and attitude.

“You didn’t tell me your damn kid was already taking missions alone,” he said, barging into the estate with his usual thunderstorm energy.

“She’s not a kid.”

“She’s tiny and polite. That is a kid.”

“She’s also faster than you.”

“What—”

“She’s also smarter.”

“Okay, now you’re just asking for a fight.”

Giyuu smiled without looking up from where he was repairing a training dummy. “Are you worried about her?”

Sanemi scowled. “No. I just don’t want to deal with you if she dies.”

“She won’t.”

“…You really believe that?”

“I believe in her.”

Sanemi let out a breath, rubbing the back of his neck.

“…That’s terrifying.”

“Love often is.”

Giyuu said it so simply that it hung in the air like a pebble dropped into still water.

Sanemi froze.

“…You love her?”

“Of course.”

He shifted.

“What about me?”

The question was quiet. Not demanding—just… honest.

Giyuu finally looked up.

The wind blew between them, rustling wisteria petals at their feet.

“I’ve known since you screamed at me for taking a hit in your place,” Giyuu said.

Sanemi’s mouth opened. Shut.

“And you’ve known,” Giyuu added, “since I let you stay.”

Sanemi crossed his arms, eyes averted. “You’re a pain in the ass.”

“So are you.”

“…I mean it.”

“I do too.”

For once, silence didn’t feel like an avoidance. It felt like breathing space.

Then Sanemi glanced sideways.

“…You’re not gonna make this easy, are you?”

“No. But I’ll make it real.”

And just like that, it was settled.

Not fireworks. Not grand gestures. Just quiet knowing, as natural as dusk falling across the estate.

⸻

Kanao returned at sundown.

There was blood on her sleeve, but none of it hers.

“I stopped it before it reached the next house,” she reported. “Used Fourth Form to corner it. Finished with Second.”

Shinobu pressed a hand to her shoulder and gave her a rare, genuine smile. “I’m proud of you.”

Giyuu said nothing, just stepped forward and held out his hand. She placed the bloodied scabbard in his palm.

He cleaned it himself.

Later, she sat beside him under the paper lanterns, both of them watching the koi drift in lazy circles.

“I thought of Kanae while I was fighting,” she whispered.

He nodded. “She’s always with us.”

Kanao leaned against him lightly. “Do you think she’s proud?”

“Yes,” Giyuu said. “Of you. Of this place. Of how far we’ve come.”

She nodded and closed her eyes.

And Giyuu thought: This is what it means to live for someone else—not out of grief, but out of growth.

⸻

That night, Giyuu found Sanemi sitting alone in the garden, sleeves rolled up, cleaning his blade with uncharacteristic care.

“You could stay,” Giyuu said.

Sanemi didn’t look up. “You offering?”

“I don’t do things halfway.”

“…You’d have to deal with me.”

“I already do.”

“You’re not scared I’ll break it?”

“What?”

“Us. This. Whatever it is.”

Giyuu stepped closer. “You might. But I trust you not to.”

Sanemi looked up then, eyes too open.

“Why?”

“Because you’re still here.”

They stood there for a long time—two worn swordsmen under a night sky full of memories and ghosts and things they hadn’t yet said.

Then, finally, Sanemi reached out. It wasn’t a dramatic kiss or a desperate clutch.

He just touched Giyuu’s wrist. Held it. Grounded them both.

“I’ll stay.”

Giyuu smiled softly. “Then don’t go.”

⸻

Years passed.

The war came and went like a storm. Some were lost—too many. Some rose in their place.

And now, in the quiet that followed, the Hashira stood different but strong.

Mitsuri, vibrant as ever, stood beside Obanai, both of them scarred and still smiling.
Muichiro, older now, steel-eyed and sure.
Gyomei, silent in prayer.
Shinobu, composed but changed—grief turned into clarity.
Sanemi, still stubborn, still fierce—but more whole than he’d ever been.
And Giyuu, calm, rooted, the last breath of water in a world healing itself.

Kyojuro was gone. A flame that lit the sky and left a crater in its place.

Tengen had retired. And occasionally sent flashy letters.

They stood together under the night sky as new crows carried new missions—less frequent now, but never absent.

Kanao stood at Giyuu’s side, no longer his tsuguko. A pillar in her own right—flower-born, water-forged.

Sanemi nudged Giyuu’s shoulder.

“You still think about drowning?”

Giyuu’s eyes didn’t leave the koi pond. “Sometimes.”

“And now?”

He looked toward the others—the people they had saved, the people they had become.

“Now I think about staying afloat. For them.”

Sanemi gave a sharp exhale—half laugh, half something else.

“You’re really gonna make me fall for you all over again.”

“You already did.”

And for the first time, wind met water without resistance.

Just the quiet rhythm of two survivors choosing each other—again, and again, and again.