Rotting Promises
---
The world had ended one and a half years ago, and it still hadn’t stopped ending.
You met Bakugou Katsuki in the ashes of what used to be a refugee camp. The air smelled of smoke and decay, the kind of stench that clung to your clothes, your hair, your lungs. His friends—those loud, bright boys who once dreamed of being heroes—were already gone. He carried their loss like shrapnel under his skin, a silent, festering wound. He never spoke their names, but you saw it in the way he flinched at sudden noises, in the way his crimson eyes scanned the horizon like he was still searching for them in the ruins.
When a massive horde swallowed the camp, you grabbed a rifle you barely knew how to use and covered his back. The recoil bruised your shoulder, the noise deafening, but you fired anyway. He noticed. Bakugou Katsuki didn’t do gratitude in words. But his grip on your arm was a little tighter after that, his steps a little slower, like he’d decided, without saying it, that you were worth the risk of slowing down.
---
For months, you survived together. He taught you how to move quietly, how to kill efficiently, how to keep going when your body screamed to stop. His lessons were brutal, his patience nonexistent, but you learned. You had to. The world didn’t forgive weakness.
In return, you taught him how to sleep for more than two hours at a time without bolting awake at every sound. Somewhere in the blood and the running and the shared cans of cold beans, he fell in love. You felt it in the way his hand lingered on your shoulder a second too long, in the way he always took the worse watch, in the way his crimson eyes tracked you like you were the last unbroken thing left on earth.
He never said it. What was the point? The dead didn’t care about confessions, and the living had no future to promise.
---
Two days ago, everything went to hell again.
The slavers had found your trail. A brutal group that kept people like cattle, their laughter sharp as broken glass. You and Bakugou ran for hours through the dense forest, legs burning, lungs raw. The trees blurred into a wall of green and brown, the ground uneven underfoot, every step a battle. A gunshot cracked through the trees. White-hot pain exploded in your left thigh as the bullet tore into your femur.
“Fuck—keep moving!” Bakugou snarled, slinging your arm over his shoulders without breaking stride. His voice was rough, but his grip was steady. You did. You ran on a shattered leg because stopping meant worse than death. The slavers’ shouts echoed behind you, their boots crashing through the underbrush like a storm.
When they finally caught up, you both fought like cornered animals. Gunfire, knives, fists, teeth. The forest floor became a slaughterhouse. Your hands wouldn’t stop shaking. Blood—yours and theirs—soaked your clothes, sticky and warm. The pain in your leg was a living thing now, gnawing deeper with every heartbeat, every stumbling step.
Bakugou half-carried, half-dragged you for hours until you found it: an old wooden house deep in the woods, its bones sagging under the weight of years. Dust swirled in the dim light as Bakugou kicked the door open, the hinges groaning like a dying man. The windows were boarded up, their blind eyes staring at nothing, as if they’d already seen too much.
---
The wound was bad. The bullet was still in there, buried deep. Bakugou tore his own shirt into strips, his movements sharp, efficient. He tied a tourniquet high on your thigh, his hands surprisingly gentle for someone who could explode with rage at any second. The cloth bit into your skin, but the pain was a distant thing compared to the fire in your leg.
“I can’t dig it out here,” he muttered, jaw tight. His eyes were dark, stormy. “You’ll get infected. I’m going out. Antibiotics, proper bandages, food—anything. You stay inside. Bar the door. Don’t make a fucking sound.”
You caught his wrist before he could leave. Your fingers were weak, trembling. “Katsuki… be careful.”
He looked at you then—really looked. Something raw flickered across his face, gone in a heartbeat. His thumb brushed your knuckles, just once, like he was memorizing the feel of your skin. “Tch. Don’t die while I’m gone, idiot.”
Then he was gone, the door slamming shut behind him like a coffin lid.
---
Two days passed in a haze of fever and pain.
You drifted in and out of consciousness on the dusty floor, your back against the wall, the rifle across your lap. The leg throbbed with every heartbeat, a relentless drumbeat of agony. Infection was already setting in; you could smell it—sweet, rotten, like death itself had settled into your bones. Thirst clawed at your throat. Hunger made your hands shake too badly to hold the gun steady. Outside, the forest whispered with the dead. You didn’t dare open the door.
On the second night, you heard them. Moaning. Scratching. The door rattled violently, the wood splintering under the onslaught. You fired through the planks until your ammo ran low, the gunshots echoing like thunder in the small space. Something heavy slammed against the door again and again until the frame splintered, and the door crashed inward with a sound like the world breaking.
You fought. You always fought. But your body was a traitor now, your legs leaden, your arms shaking. The knife in your hand felt like a hundred pounds, but you swung it anyway, because giving up wasn’t an option. Not when Bakugou was still out there. Not when the world had already taken everything else.
A zombie—rotting, jaw unhinged, its eyes milky white—lunged at you while you were trying to crawl away. Its teeth sank deep into your shoulder. The pain was blinding, a white-hot agony that stole your breath. You screamed, shoving your knife up under its chin, twisting until it went limp. But the damage was done. Blood poured down your chest, mixing with tears that wouldn’t stop falling.
You dragged yourself back against the wall, hand clamped uselessly over the bite, sobbing quietly as the world blurred. The fever burned through you, turning your skin to fire, your thoughts to ash. Your fingers twitched against the floor, jerky and uncoordinated, like they were already forgetting how to be human.
---
Bakugou returned under a cold, indifferent moon.
His backpack was heavy—painkillers, antibiotics he’d pried from an abandoned pharmacy, canned food, fresh bandages, even a half-bottle of whiskey he planned to use for sterilization. Two days of running, killing, and barely sleeping, all so he could come back to you. The weight of it pressed into his shoulders, a physical reminder of the promise he’d made to himself: She’s going to be okay. She has to be.
The broken door stopped him cold.
Zombies wandered between the trees, drawn by the noise, their movements sluggish but relentless. He killed them in silence, his body moving on instinct, explosions of movement and knife work, rage boiling under his skin. His breath came in ragged bursts, like he’d been running for hours. Maybe he had. When the last one dropped, he stepped inside, his boots crunching on broken glass.
The smell hit him first—blood, rot, gunpowder. Thick. Choking. His stomach twisted.
Then he saw you.
You were slumped against the far wall, legs splayed, the tourniquet on your thigh dark with old blood. A dead zombie lay at your feet, your knife still buried in its skull. And your left shoulder… fuck. The flesh was torn open, teeth marks clear, blood still oozing, soaking into your shirt. Your head lifted weakly, your eyes glassy, pupils dilating unnaturally. Tears cut clean tracks through the dirt and blood on your face.
“Katsuki…” Your voice was a broken whisper, barely a breath.
He crossed the room in three strides and dropped to his knees beside you. His hands hovered, afraid to touch, afraid you’d shatter. The backpack spilled forgotten onto the floor, its contents scattering like his hopes. His breath hitched, his chest tightening like a vice. For a second, he didn’t move. Didn’t blink. Then his fingers were on your face, tracing the line of your jaw, like he was trying to memorize the shape of you before it was too late.
“No,” he snarled, voice cracking. “No, no, you stupid— I told you to stay quiet, I told you—”
You tried to smile. It came out as a grimace. “They broke in… I tried. I really tried.”
He pressed his palm over the shoulder wound, as if he could push the infection back inside, undo the damage. His other hand cupped the side of your neck, thumb brushing your jaw. His eyes were wide, wild, shining with something he’d never let himself feel fully until this moment—something raw, something broken.
“I got the meds,” he said hoarsely. His voice was rough, desperate. “I got everything. We can fix this. Just—don’t you fucking dare leave me too.”
You shook your head slowly. The fever was burning you up from the inside. You could already feel the sickness spreading, the unnatural hunger stirring beneath the pain, coiling in your veins like a serpent. You knew what came next.
“Katsuki… it’s too late.” Your hand found his, sticky with blood. “I can feel it. I’m going to turn. I don’t want to hurt you. Please…”
His breath hitched. The great Bakugou Katsuki—loud, angry, unbreakable—looked shattered. His face crumpled, his usual defiance replaced by something far more fragile. He pulled you against his chest, arms wrapping around you like iron bands, burying his face in your hair. You could feel him trembling, his body wracked with silent sobs.
“I should’ve said it too,” he whispered fiercely. His voice was a blade, sharp with regret. “Every damn day. I love you. I love you, you hear me? Don’t you dare make me do this.”
You clung to him as long as you could, breathing in the smell of smoke and sweat and him. The forest was quiet outside now. Just the wind and the distant moans, like the world itself was mourning.
“I’m sorry,” you breathed against his neck. “Thank you… for everything.”
He held you tighter, his fingers digging into your back like he could anchor you to the living world. Minutes stretched into eternity. Your breath came in shallow gasps, each one weaker than the last. The fever spiked, turning your skin to fire, your thoughts to ash. Your fingers twitched against his back—jerky, uncoordinated, like they were already forgetting how to be human.
Bakugou pulled back just enough to look at your face. Your eyes were glassy, pupils dilating unnaturally. A low, hungry sound escaped your throat, a sound that didn’t belong to you anymore.
His hand moved to the knife at his belt. Tears—actual tears—slid down his cheeks, mixing with the grime, cutting through the dirt like rivers of regret. He pressed his forehead to yours one last time, his breath hot against your skin.
“I’m sorry,” he choked out, his voice breaking. “I’m so fucking sorry.”
The blade slid between your ribs, quick and merciful.
Your body jerked once, then went still in his arms.
---
Bakugou didn’t move for a long time. He held you as the house grew colder, as your blood cooled against his chest, rocking you gently like he could somehow keep you from slipping away. His fingers traced the line of your jaw, memorizing the shape of you, the weight of you, the feel of you. The tears came then, hot and silent, soaking into your hair, your skin, like he could drown the world in his grief.
When he finally laid you down on the floor, he closed your eyes with shaking fingers. He took the backpack he’d fought so hard for and set it beside you like an offering, a sacrifice to a god that no longer listened. The whiskey bottle rolled out, catching the dim light, its amber liquid sloshing like a mockery of warmth.
Then he stood up, his legs unsteady, his body heavy with a grief that threatened to drag him into the earth. He picked up his rifle, the weight familiar, grounding. The forest loomed outside, dark and endless, its branches swaying like skeletal hands.
He didn’t look back. He couldn’t. If he did, he’d see the ghost of you in every shadow, hear your voice in every whisper of the wind. And that was a pain even Bakugou Katsuki couldn’t outrun.
The forest swallowed him whole, its branches closing behind him like a coffin lid.
And moving was the only thing left.