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Chapter Text

Kaeya

The sound of steel on steel rang sharp against the midnight air.

Kaeya twisted his blade in a tight arc, sparks flaring as he parried the strike of a hilichurl’s crude axe. His boots slid across the cobblestones, breath misting in the chill night as he pivoted, driving his opponent back with practiced ease. The creatures had been bold tonight—too bold—wandering close to Mondstadt’s walls as if they no longer feared the Knights of Favonius’ patrols.

He let his sword rest at his side for half a heartbeat, the corner of his lips curling in a faint, amused smile. “You really should know better,” he said softly, though his voice carried enough to make the hilichurl pause.

The pause was fatal.

One clean strike ended it, and Kaeya flicked the blade free of blood before turning on his heel. But his smile faded as quickly as it had come. Because the street was still too quiet. Because the night air still tasted wrong. Because someone—or something—was watching.

His hand tightened on the hilt.

“Come now,” Kaeya murmured, scanning the rooftops with a sharp eye. “If you’ve gone through the trouble of stalking me, the least you can do is say hello.”

From the shadows, a figure stepped into the pale light of the street. Red hair caught the moon’s glow, unmistakable even in the dark.

Kaeya’s expression flickered, just briefly, before he schooled it into something lighter. “Ah. So the mysterious stalker turns out to be none other than Master Diluc himself. Tell me—have you taken to following me around at night, or did fate simply feel like a joke tonight?”

Diluc didn’t answer right away. His arms were folded, gaze heavy with something Kaeya couldn’t quite pin down. “You were careless,” he said finally, voice even.

Kaeya laughed softly, tilting his head. “Careless? Me? You wound me, brother. I thought my swordplay was rather dazzling.”

“You shouldn’t be out here alone.”

That earned a pause, but Kaeya recovered quickly, grin widening. “Ah, so it’s concern, then. Don’t tell me you’re losing sleep over little old me.”

Diluc’s jaw tightened, and for a moment it seemed like he might deny it. Instead, he glanced away, choosing silence.

Kaeya let the moment linger before giving a small shrug. “Well, whatever your reason, you can rest assured. I’m still alive, and I’ll be fine without a shadow trailing after me. But… how thoughtful of you, truly.” His tone was light, but his words cut sharp enough to end the conversation.

He turned, boots clicking against the cobblestones as he started toward the gates of Mondstadt. His hand brushed absently against his side as he walked, but he didn’t notice the warmth seeping beneath his glove, or the way the shallow scratch from earlier ached more than it should.

Behind him, Diluc stayed rooted to the spot, his unreadable gaze following Kaeya until the night swallowed him whole.

Chapter Text

Kaeya

The morning sun slanted through the shutters, warm and golden, but Kaeya felt anything but warm.

He stirred with a groan, the room tilting faintly around him. His head ached, a heavy, pulsing rhythm that didn’t quite match the usual aftermath of a long night—or a few too many glasses of wine. He pushed himself up slowly, one hand pressed to his temple, the other bracing against the edge of the bed.

“Dizzy? Tch. You’re getting soft,” he muttered to himself, though even the sound of his own voice felt too loud in his skull.

It was then the sharp sting along his side reminded him of the fight. His brow furrowed, a flicker of unease cutting through the haze as he tugged at the fabric of his shirt.

The moment the hem lifted, his breath caught.

The shallow scratch he barely remembered earning now pulsed with something unnatural—angry lines of purple radiating outward like veins, creeping tendrils of abyssal energy twisting beneath his skin. It looked alive. Hungry.

For once, Kaeya was silent. His fingers hovered just above the mark, trembling slightly before he forced them still.

“…Shit.” The word was exhaled more than spoken. His usual easy smile was nowhere to be found.

He dropped the shirt quickly, as if covering it would make it disappear. But the lingering ache beneath the fabric only confirmed what he already knew. That was no ordinary wound.

Brows knitted, he leaned back against the headboard, suddenly aware of how weak his body felt—how foreign. “Did that hilichurl… poison its blade?” he wondered aloud, though deep down he already knew the truth. He’d felt this kind of corruption before, faint whispers of it in the darker corners of Mondstadt’s history. This wasn’t poison.

This was something far worse. Abyssal.

Chapter Text

Kaeya

The days blurred together in a haze of forced smiles and quick excuses.

At first, it was manageable—just dizziness, a faint ache at his side. He hid it behind a careless smirk, slipping past Jean’s sharp eyes with practiced ease. He still showed up to patrols, still filled the tavern with easy laughter, still played the role of Mondstadt’s Cavalry Captain.

But each night the pain deepened.

The purple tendrils crept further with every sunrise, curling over his ribs, climbing toward his chest. His strength waned. His blade grew heavier. His charm faltered. When he was alone, his breath came ragged, sweat dampened his collar, and his hands shook until he clenched them tight enough to leave crescent marks in his palms.

He told no one. Not Jean. Not the Knights. Certainly not Diluc.

Until the fourth morning.

On patrol, near the edge of Dawn Winery’s vineyards, Kaeya staggered mid-step, one hand braced on his knee as if the weight of his own body had become too much to carry. The world swam, air thin in his lungs, pain burning like fire beneath his skin. The tendrils had spread across his chest now, curling faintly up his neck where no high collar could hide them.

He couldn’t go back to Mondstadt. Not like this. Jean would see. Everyone would see. He can’t let them worry…

And yet… his legs carried him forward, weak but determined, toward the one place he’d sworn not to rely on.

The manor loomed ahead, its windows lit faintly against the dawn. He stumbled up the steps, nearly collapsing as his shoulder hit the heavy doorframe. His breath rattled, shallow and broken, as he raised a trembling fist and knocked.

It was barely more than a scrape of knuckles against wood.

But it was enough.

The door opened.

Diluc stood there, framed by the glow of the manor’s light, his crimson hair tousled from the early hour. His eyes widened instantly, the stoic mask shattering at the sight before him.

Kaeya leaned heavily against the door, every ounce of bravado gone. His lips curved into the faintest of smirks, but his voice was nothing more than a hoarse whisper.

“…Need a favor, brother.”

And then his knees gave out.

Chapter Text

Diluc

Normally Elzer or one of the maids would have answered the knock. Diluc hadn’t expected to rise from his seat at the table, hadn’t expected the chill of the wood under his palm as he pulled open the door himself.

And he certainly hadn’t expected to see Kaeya.

His breath caught in his throat, the air around him suddenly thin. Kaeya leaned heavily against the doorframe, his posture collapsing under its own weight. Diluc’s sharp eyes immediately fell to the window of his uniform that showed his chest where pale skin was marred by something unnatural.

Purple. Veins, tendrils, crawling up from his chest to his neck like a brand of corruption. His skin was slick with sweat, complexion ashen, his body trembling with every shallow breath.

“…Need a favor, brother,” Kaeya rasped.

Then his knees buckled.

“Kaeya!” Diluc’s voice cracked against the manor walls as he lunged forward, catching his brother just before he struck the ground. The weight in his arms was startling—too light, too fragile. Kaeya’s head lolled against his shoulder, his visible eye rolling back, lids fluttering closed.

Diluc’s chest tightened, panic tearing through him. “Adelinde!” His voice thundered, urgent, desperate. “Adelinde, now!”

His words echoed through the halls, footsteps scrambling somewhere in the distance, but he barely heard them. His world narrowed to the figure in his arms.

He looked down again, heart hammering. Kaeya’s breathing was wrong—shallow, erratic, each inhale uneven as if his body fought against itself. The corruption pulsed faintly with each beat of his heart, spreading like ink through water.

“Stay with me,” Diluc muttered, his voice rough, almost pleading as he shifted Kaeya closer against him. His hand pressed lightly against his brother’s back, feeling the tremors racking through him. “Archons, stay with me…”

When Adelinde came running into the foyer, the Master of Dawn Winery—always calm, always composed—was on his knees, clutching his brother as though he was afraid to let go.

Chapter Text

Diluc

“Master Diluc,” Adelinde’s voice was urgent but steady, the way it always was in times of crisis. “We must get him upstairs. He needs a bed, not the floor.”

Diluc’s grip only tightened around Kaeya, his arms locked as if letting go meant surrendering him. “No. Not until we—just bring what we need here. Go get help.” His voice was sharp, commanding, but the tremor beneath it betrayed him.

Adelinde knelt swiftly beside him, eyes hardening. “You’ll do him no good keeping him in the foyer. Please, Master Diluc. He is burning alive in your arms. If you care for him—move him.”

For a long, tense heartbeat, Diluc couldn’t breathe. The words scraped against his chest, tearing at something raw. But he looked down at Kaeya—his pallor, the sweat slicking his hair to his face, the ragged, uneven rise and fall of his chest—and the fight bled out of him.

His jaw clenched. “…Fine.”

In one smooth motion, he lifted Kaeya, holding him close as though every jostle might break him further. His brother’s head lolled limply against his shoulder, body unnervingly light as he carried him up the grand staircase.

They laid him down on the bed in one of the guest rooms. Almost immediately, Kaeya began to thrash, tossing and turning, low sounds escaping his throat—half-whimpers, half-choked cries. His hands clawed weakly at the sheets, his body twisting as though caught in a nightmare too real to wake from.

Diluc froze for only a second before pressing his palm firmly to Kaeya’s shoulder. “Kaeya,” he called, voice low but urgent, “stop—don’t—” But it was no use. His brother’s eye stayed shut, lashes damp, his body shuddering with pain Diluc could do nothing to ease.

Adelinde reappeared at the door, a basin of water balanced in her arms and a cloth draped over the side. Before she could set it down, Diluc reached for it, snatching the rag with trembling hands and dunking it into the cool water. He wrung it out quickly and pressed it to Kaeya’s forehead, then his cheek, then his throat, desperate to calm the fever radiating from him.

Kaeya whimpered at the touch, curling faintly toward the coolness, and Diluc’s chest ached with something sharp and unbearable.

“Call for Jean,” he ordered, his voice rough, low, but filled with steel. “Send Elzer to Mondstadt. Now.”

Adelinde gave a firm nod and disappeared again, footsteps hurried down the hall.

Diluc dragged the chair closer to the bed, never lifting the rag from Kaeya’s overheated skin. His gloved hand brushed across his brother’s damp hair, pushing it back from his face. “Just hold on,” he whispered, more to himself than anyone else. “Jean will know what to do. Just… hold on, Kaeya.”

Chapter Text

Diluc

The room was unbearably quiet, save for the ragged sound of Kaeya’s breathing.

Diluc sat rigid in the chair beside the bed, every muscle in his body taut with helplessness. The cool rag in his hand had gone warm again, so he dipped it back into the basin, wrung it out, and laid it across Kaeya’s brow once more. The Cavalry Captain—his brother—shifted restlessly, his face tight with pain even in unconsciousness.

“Always so stubborn,” Diluc muttered under his breath, his voice low, raw. “Always trying to shoulder everything alone. And look where it’s brought you.” His hand, rough from swordwork, lingered against the damp skin of Kaeya’s temple.

Kaeya flinched, his body jolting against the mattress as a broken sound escaped his lips. It was hardly a word, more of a pained whimper, but it struck Diluc like a blade. He caught his brother’s hand as it twisted in the sheets, squeezing tightly.

“Kaeya. Listen to me. You’re not alone here.” His voice cracked despite his effort to keep it steady. “Not this time.”

But the younger man didn’t stir. His body arched faintly, twisting with invisible torment. Diluc leaned forward, his forehead nearly touching Kaeya’s as his voice dropped to a harsh whisper.

“I lost you once already. I will not—Archons help me—I will not let it happen again.”

Kaeya whimpered again, turning his head to the side, breath coming faster now. Diluc pressed the rag to his throat, desperate to cool the fever burning through him. He cursed himself for not noticing sooner, for all the years of cold silence that had built this distance between them. For being the last person Kaeya had turned to—yet the only one he had in this moment.

When Kaeya thrashed again, Diluc gritted his teeth, pressing a steady hand to his chest to still him. The motion made him pause—Kaeya’s shirt clung damply, every breath rasping against the sweat-soaked fabric. It wasn’t enough. He needed him out of these clothes before the fever boiled him alive.

With stiff, unsteady hands, Diluc forced himself to work. He stripped Kaeya from the Knights’ uniform, jaw tight at how light and frail he felt in his arms. Once Kaeya was down to his undershirt, Diluc tore the ruined fabric away, replacing it with clean linen, then eased him into loose trousers. The motions were careful, almost reverent, though his chest constricted with guilt at how vulnerable Kaeya looked—how fragile.

And then Diluc saw it.

The wound.

Just a shallow scratch along Kaeya’s side—small, almost laughable in its simplicity. But it was no ordinary wound. Around it, the skin was blackened and festering, purple tendrils of corruption spreading outward like roots burrowing through the flesh. It pulsed faintly, alive with some abyssal energy he did not understand.

Diluc’s breath caught. His gloved hand hovered just above it, fingers trembling. He had seen horrors on the battlefield, in the Abyss—but nothing struck him like this. Nothing had ever felt so personal.

“Archons…” His voice broke, the word torn from his chest. “All this—from this.”

Kaeya whimpered again, curling faintly to the side as if to shield the wound. Diluc immediately pressed the cloth to his brow again, leaning close, whispering hoarsely: “Stay with me. I don’t care what it takes—I’ll burn the world down if I have to, but you will not leave me here. Not again.”

The door opened behind him.

“Master Diluc—” Jean’s voice, breathless from the ride.

He didn’t even turn. “He’s here.” he rasped, tightening his hold on Kaeya’s hand.

Jean strode forward, her eyes widening the moment they fell on Kaeya’s pallor, the blackened veins curling up his torso, the way his breath rattled in his chest. She dropped her bag onto the table by the bed, gloves already sliding onto her hands.

“Diluc—step back,” she said firmly, though her own voice trembled.

But Diluc did not move. His hand still clutched Kaeya’s, his body bent protectively over his brother. His voice came low, hard. “Fix him.”

Jean swallowed, nodding. “I’ll do everything I can.”

Chapter Text

Kaeya

Heat. That was the first thing Kaeya felt when the haze cracked open again—heat, pressing into his skin, burning through his veins like fire. He gasped, though the sound came out weak, ragged, his chest straining for air that never felt enough.

“…Diluc?” His voice broke, hoarse and barely audible. His visible eye fluttered open, but the room swam and bent, shapes blurring together.

Above him, a familiar face appeared. Crimson hair, drawn features, eyes wide with something Kaeya rarely saw there—fear. Diluc’s fear.

“You’re fine,” Diluc’s voice said, sharp but low, like he was speaking through clenched teeth. “I’m here. Just—don’t move.”

Kaeya wanted to ask why . Why was he so warm, why did every breath feel like drowning, why did Diluc look at him like that? But the haze pulled him under again before the words could form.

⸻

The next time he surfaced, voices pressed against the edges of his consciousness.

“Can’t… heal…” Jean’s voice—Kaeya knew it, faint but strained.

“Try again,” Diluc snapped, closer this time, sharp as steel.

“Abyssal,” Jean’s tone dropped, hushed but urgent.

Another pull of darkness.

⸻

He woke again to hands on his shoulder, steady, grounding. His chest felt like it was on fire, every inhale rasping painfully. He turned his head weakly, and through the blur, Diluc was there. Always there.

Kaeya swallowed, his throat raw. “…Why do you… look scared?” His voice cracked on the last word.

Diluc’s expression flickered, but his grip on Kaeya’s hand tightened. “Because you’re an idiot,” he said harshly, though his voice wavered. “And you don’t get to leave me. Not like this.”

Kaeya blinked, struggling to focus, but the heat roared louder in his skull, dragging him down again.

⸻

The final fragments before the darkness closed in were worse.

“Corruption—” Jean’s voice, panicked.

“Chasm…” another murmur, filled with dread.

Kaeya didn’t understand. He only knew fear. And warmth. Too much warmth. His trembling hand reached blindly, searching, and it was caught immediately—Diluc’s hand closing firmly around his own.

“I’ve got you,” his brother’s voice murmured, raw and unsteady, the last thing Kaeya heard before the blackness swallowed him whole again.

Chapter Text

Diluc

The corruption was spreading.

Diluc’s chest constricted as his eyes tracked the dark veins now curling up Kaeya’s neck, webbing across his cheek like cracks in porcelain. It looked wrong—unnatural, an infection that no healer’s hand could cleanse. His stomach turned, and for the first time in years, fear settled heavy and choking in his throat.

He tore his gaze from Kaeya only long enough to look at Jean. “According to Albedo, it’s a lumenstone we need? From the Chasm in Liyue? Cleanse abyssal corruption.” His voice was low, tight, almost unrecognizable even to himself. “Can he even last that long?”

Jean’s lips pressed into a thin line. “Albedo anticipated this. He and Eula left yesterday morning, the moment he saw the first signs of corruption. They’ll bring back what we need.” Her voice was steady, but her eyes betrayed her worry.

Diluc swallowed hard, his gaze snapping back to Kaeya. He wanted to believe Jean. Needed to. But what he saw in front of him was enough to unravel any certainty.

Kaeya had stopped thrashing.

At first, Diluc thought it a mercy—no more weak, pained cries or restless twisting. But the stillness was worse. His body lay limp against the sheets, his chest barely rising, breaths shallow and rattling as though each one might be his last. His skin burned beneath Diluc’s touch, fever spiking so high it was almost unbearable to feel.

“Kaeya,” Diluc rasped, leaning over him, shaking his shoulder gently. “Don’t you dare—don’t you dare .”

Jean pressed a hand to Kaeya’s wrist, her expression paling. “His pulse—Archons, it’s too weak—”

“No.” The word was a growl torn from deep in Diluc’s chest. His hand slid to cup Kaeya’s jaw, forcing his brother’s head to face him. “Look at me. Breathe. Just—breathe.” His voice broke, sharp and desperate. “Please.”

Kaeya’s breaths came slower still, each one a rattling gasp that made Diluc’s blood run cold. The corruption pulsed in time with his failing heartbeat, creeping further with every passing second.

Diluc had never prayed. Not to Barbatos, not to Morax, not to any Archon that had ever stood over this land. His faith had died long ago.

But now, with his brother burning in his bed and slipping further from his reach, Diluc bowed his head, eyes shut tight. If there’s any mercy left in this world—if any of you are listening—don’t take him from me. Not like this. Not when I just got him back.

His grip on Kaeya’s hand tightened, as if sheer willpower could tether him to life.

“Albedo. Eula.” His voice was hoarse, raw with desperation as he glanced toward Jean. “They’d better make it back in time. They have to.”

Jean didn’t answer. Her silence was answer enough.

And so Diluc prayed harder, to gods he had never believed in, while the brother he had sworn to hate fought for every single breath beside him.

Chapter Text

Diluc

Two days.

Two days of sitting vigil at his brother’s side, watching the corruption crawl mercilessly across Kaeya’s body like ivy choking the life from a wall. What had begun as faint lines at his chest now spread everywhere—blackened veins lacing up his neck, curling over his cheek, slipping down the length of his arms.

Two days of fever so high that every rag Adelinde pressed to Kaeya’s brow dried within minutes.

Two days of breath so faint, so shallow, Diluc found himself leaning close at intervals just to feel the whisper of air against his cheek—if it was even there at all.

Kaeya was pale now, far too pale. Sweat dampened his hair, plastering blue strands to his face. His lips had lost their color, his chest barely stirred beneath the sheets. He looked like death already had him in its grip, and the sight hollowed Diluc out from the inside.

He had not left the room. Not for food. Not for sleep. Not even to change. His world had shrunk to the space of Kaeya’s bedside, his gaze fixed on the fragile rise and fall of his chest.

The sound of hurried footsteps broke the silence. Then the door burst open.

“Master Diluc!” Jean’s voice, relieved and urgent. Behind her, two figures stepped in—Albedo, calm but tight-jawed, and Eula, still in half-battered armor, snow melting from her pauldrons.

They had returned.

Diluc shot to his feet, the chair skidding back. “Do you have it?”

Albedo didn’t waste words. From his satchel, he withdrew a crystal, its faint glow pale and cool—a lumenstone, mined from the deepest veins of the Chasm. Without hesitation, he set it against the bedside table, lifted a small hammer, and crushed it down to dust. The powder shimmered faintly, scattering across the wood like starlight.

“Hold his head,” Albedo instructed, calm but urgent.

Diluc obeyed instantly, sliding his arm beneath Kaeya’s shoulders, lifting him slightly. His brother’s head lolled against him, too light, too limp.

Albedo tilted the powdered lumenstone into a small cup of water, stirring it until the liquid faintly glowed, then tipped it carefully against Kaeya’s lips. “Swallow,” he murmured, voice sharp. “Come on. Swallow.”

Some trickled down, but more dribbled out, sliding uselessly down his chin.

“Archons—” Diluc’s voice cracked, panic clawing at his chest as he adjusted Kaeya, thumb brushing across his throat, willing him to react. “He’s not—he can’t—”

“Patience,” Albedo said firmly, though his own eyes flicked nervously to Kaeya’s pale face.

The room fell into silence. No one moved. Every breath—every faint flicker of movement—was scrutinized, prayed over, begged for.

Diluc’s hand clutched Kaeya’s, squeezing desperately, his own heartbeat roaring in his ears. “Come on,” he whispered, his forehead pressed briefly to Kaeya’s damp hair. “Don’t you dare leave me.”

And then—

The faint, fragile heartbeat beneath Diluc’s palm stuttered.

The next moment, it stopped.

Kaeya’s heart stopped.

Chapter Text

Diluc

“Kaeya—no, no, no!”

Diluc’s voice cracked as he pressed down hard against his brother’s chest, trying to force life back into him with sheer will. Every push was frantic, ragged, his breath coming harsher than Kaeya’s ever had. “Breathe! Don’t you dare leave me—Kaeya!”

Jean’s hand caught his arm, firm but trembling. “Diluc—stop—”

He snarled, wrenching his arm free. “Don’t tell me to stop!” His palms pressed again, harder, desperate enough to bruise. “He’s not gone—he’s not—”

Jean’s eyes filled, but her voice held steady. “Diluc. He’s gone.”

It hit him like a blade through the chest.

Albedo moved quietly, carefully, a white sheet in hand. His gaze was heavy, unreadable, but determined. “We need to—”

Diluc snapped.

The moment Albedo reached for Kaeya’s face, Diluc shoved him back so hard the alchemist stumbled into the wall. “Don’t you touch him!” His voice roared through the room, raw and broken, reverberating in his own ears. He turned, putting his body between them and Kaeya’s still form, shoulders squared like a beast cornered.

His arm lashed out blindly, striking the nightstand beside the bed. Wood splintered under the force, shards skittering across the floor. He seized one of the broken legs, hand shaking, then summoned fire with his Vision. In an instant, the wood was aflame, crackling and hissing, a makeshift torch trembling in his grip.

The heat seared his skin, but he didn’t care. He brandished it at them like a weapon, his back pressed to the bed. His voice ripped free, a guttural, desperate snarl. “Stay away! Do you hear me? Stay the hell away from him!” His chest heaved, firelight flickering wild across his face. “He’s not gone—he’s not—Archons, please—”

His throat broke, words tumbling out softer, cracked with grief. “He’s my little brother. I love him. Don’t take him from me…”

The room froze. Jean’s eyes shone with tears, Adelinde’s hands trembled against her apron. Eula’s breath hitched audibly, a hand covering her mouth. Even Albedo, steady as stone, faltered.

Then—

From behind him, weak and raspy, came a sound.

“Y’mean… that?”

Diluc’s heart stopped.

Every head in front of him snapped toward the bed. Jean gasped aloud, her hands flying to her lips. Adelinde choked out a sob. Eula stumbled back a step, blue eyes wide. And Albedo whispered, disbelieving: “No way…”

Diluc turned.

And there—half-sat up, trembling, propped weakly on his elbows—was Kaeya. His eye glazed, his lips pale, but his chest rising with shallow, living breaths.

Very much alive.

Chapter Text

Kaeya

The world swam back into focus slowly, like surfacing from the bottom of a frozen lake. His chest ached, his head throbbed, and for a moment Kaeya wasn’t sure if the flickering light he saw was real or some cruel trick of fever and corruption.

But then he heard it.

Diluc’s voice—ragged, breaking, pleading.

“Please… he’s my little brother. I love him. Don’t take him from me…”

Kaeya’s eye fluttered open. The ceiling blurred overhead. His throat scraped with dryness, but somehow, the words slipped out anyway: “Y’mean… that?”

The sound of wood clattering to the floor snapped through the silence—Diluc had dropped the makeshift torch.

In the next heartbeat, Kaeya was pulled upright—too quickly, his head spinning—but then he was enveloped in something warm and fierce. Diluc’s arm pressed against his lower back, hauling him close, while his other hand cradled the back of his head, tucking him against his chest as though he could shield him from death itself.

The hug was crushing, desperate, trembling. Kaeya’s chest hurt more from the force than the corruption. But Archons—he didn’t care. It was the safest he’d felt in years.

When Diluc finally pulled back, Kaeya blinked up at him through hazy vision. Tears glimmered in his brother’s eyes—real, unhidden tears. It almost stole his breath.

He glanced around the room, disoriented, and noticed the broken nightstand, the shards of wood scattered across the floor, smoke curling faintly from the charred remains. His brows knit faintly. “Wha—” he began, his voice weak, the question caught in his throat.

But before he could finish, a violent lurch rolled through his stomach. His complexion turned sickly green.

“Bucket,” Adelinde said quickly, moving with surprising speed. She pressed it into his hands just in time.

Kaeya gagged, body heaving, and then vomited—thick, dark-purple liquid spilling out, viscous and wrong, reeking faintly of abyssal rot. His body shook with the effort, every muscle trembling.

Diluc’s arm steadied him, broad hand braced firmly at his back. His face twisted with horror. “What—what is that?”

Albedo stepped forward, gaze fixed on the bucket with scientific detachment. “The corruption leaving his body.” He adjusted his gloves, voice calm but certain. “It means the lumenstone is working. This is a good sign.”

Kaeya’s eye half-lidded, hazy. He turned weakly toward Adelinde, who hovered nearby with a cloth to wipe his mouth. “…Sleepy,” he whispered, slurring faintly, exhaustion dragging him down again.

Adelinde gave him a soft, motherly smile, helping him lie gently back against the pillows.

Diluc leaned close, his voice low and steady now, though his hand still trembled slightly as he brushed damp strands of blue hair away from Kaeya’s eye. “Get some sleep,” he murmured.

For once, Kaeya didn’t argue. His lashes lowered, and within moments, he drifted back into a fragile but peaceful slumber.

Chapter Text

Kaeya

Kaeya woke again, this time not to heat or delirium, but to the sharp ache of awareness. His head pounded mercilessly, a steady throb behind his eye, and his throat felt like it had been scoured raw. He groaned, shifting against the pillows, every muscle sluggish and heavy as stone.

The dim glow of the lamp on the nightstand told him it was late. Or perhaps very early.

But more telling than the lamp was the figure seated beside his bed.

Diluc.

He was slumped in the chair, cape discarded, shirt rumpled, the familiar fall of crimson hair loose around his face. His arms rested on the edge of the bed, his head bowed, though the moment Kaeya stirred, his brother’s head lifted sharply—ever alert. His eyes were tired, rimmed red, but still burning with intensity.

“You’re awake.” The words came quiet, controlled, though the relief was undeniable.

Kaeya blinked at him, lips quirking faintly. “Lucky me.” His voice cracked, but he tried for levity anyway.

Diluc leaned forward, searching his face for any sign of relapse. “The corruption… it’s gone now. Mostly. The veins have receded.” His gaze flicked briefly to Kaeya’s arms, then back. “But you’ll still be weak. Sick, for a while.”

Kaeya hummed, eyelid heavy but a smirk tugging faintly at his lips. “Worse than any hangover I’ve had.”

The joke was feeble, but it was his way—banter, deflection, the old Kaeya shield.

But Diluc didn’t laugh.

Instead, silence settled between them. Silence heavy enough to make Kaeya’s smirk falter.

And then, softly, almost too soft, came words Kaeya hadn’t expected.

“…I’m sorry.”

Kaeya’s visible eye widened slightly. Of all the things he thought Diluc might say, an apology was never among them.

The pounding in his head was nothing compared to the sudden tightness in his chest.

Chapter Text

Kaeya - End

Kaeya blinked at his brother, unsure if his fever had returned or if his ears were simply failing him.

There were only three possible explanations, really.

One: he’d misheard. Poison had spread to his ears now.

Two: he’d died, and this was some strange afterlife where Diluc of all people apologized.

Three: he was still delirious, and the world was playing tricks on him.

Because there was no way Diluc had just said those words.

Kaeya smirked faintly, voice scratchy but teasing. “I must still be half-delirious. Did the great Master Diluc really just apologize to me?”

But Diluc didn’t bite at the jest. His gaze stayed steady, firm, far too raw for Kaeya’s comfort.

“I mean it.” His voice was low, quiet but deliberate, every syllable sharp with truth. “I’ve treated you poorly since I came back to Mondstadt. I told myself it was righteous, that I had every reason to hate you. But I was blind.”

He drew in a breath, gloved hands curling into fists against his knees. “I’m ashamed that it took nearly losing you for me to realize how truly blind I’ve been.”

Kaeya’s smirk faltered.

For once in his life, words abandoned him. Shock rooted him in place. Then warmth—fierce, overwhelming—swelled through his chest, so sharp it almost hurt. He was happy. So happy. Happier than he had any right to be.

So happy, in fact, that his stomach lurched violently.

“Oh, Archons,” Kaeya muttered, turning green.

In a heartbeat, a bucket materialized into his lap. Kaeya doubled over with a heave, gagging as more of the thick, viscous corruption spewed out, staining the bottom of the pail a dark, hideous purple.

His body shook with the effort, panting heavily as he wiped his mouth with a trembling hand. “Ugh.” He shoved the bucket weakly toward Diluc, his lips twitching upward in the faintest, exhausted grin. “If you’re that sorry, you can take care of this for me.”

Diluc stared at him for a long moment before rolling his eyes skyward with a noise halfway between exasperation and relief. He stood, lifting the foul-smelling bucket, and turned toward the door.

“Luc?” Kaeya’s voice was softer now, almost tentative.

Diluc paused in the doorway, shoulders tense.

Kaeya’s visible eye softened. His smile—weak, tired, but real—trembled on his lips. “I forgive you.”