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Katsuki was not in Tokyo when it began. He was on an away-mission with his team in southern Japan.
First came the false twilight. Something covered the skies with a dull, grey haze even though it was mid-morning and the weather forecast called for clear skies. Katsuki’s initial thought was that a volcano must have erupted, spewing its belly’s contents up in the air. He coded his team to alert status. A natural occurrence or a villain attack: both would require their assistance.
News and hero reports— back when they were still getting them— were sketchy in the beginning. No one could confirm a volcanic eruption. And it seemed the dark haze covered most of Japan. They soon learned that it covered most of the globe.
10 hours later, the deaths began.
Hundreds, thousands, hundreds of thousands of people died through the night. It was an infection of some kind. It ate a person from the inside. It was painful, physically gruesome, and highly contagious. It wiped out families, neighborhoods, entire villages; spread by people who didn’t know they were sick until they began throwing up— their organs liquefying inside— and soon wished for death.
It was airborne, they suspected. Or possibly, it spread through contact. There wasn’t really time to speculate, much less diagnose. Those who could, donned masks and stayed inside. People talked nervously of quarantine protocols while gloves and hazmat suits came out. Too many people were dying, much too fast. Hospitals were first overwhelmed, then infected.
The Prime Minister, most of the members and staff of the Diet, all succumbed. Everyone who attended the emergency briefing held by the Japan Heroes Association— 108 pro heroes: gone in the blink of an eye.
24 hours later, just as true darkness fell, the real nightmare began.
Those who had died, their corpses deformed and bloated by their death, reanimated. It began in hospital and city morgues, in funeral homes, in ice rinks where the too-many-dead-bodies had been temporarily stored. It began in houses where people were grieving their loved ones in rooms next door, until those same loved ones got up, and with hellish groans and with gnashing teeth and inhuman strength, tore them apart.
It isn’t difficult to kill the fuckers. Bash their skulls in, pierce their brains with a large enough hole, or separate the head from the neck. The difficulty lies in their sheer numbers; their inability to feel fear or pain; the fact that they keep coming, groaning and crawling on the ground, when half their body had already been blasted away.
The hard part is that Katsuki and his team are only human. This is worse than fighting nomus, which they all know to be people that had been experimented on, but don’t look human anymore. These… things are all too human in appearance, despite their mangled, horrific states. Some are children. They all still wear the clothes they died in— jeans, suits, pajamas, summer dresses; they’re covered in filth and gore but all too recognizably human.
The soul-crushing part is knowing that this is happening all over the world. That their friends and family back home had most likely already succumbed, if not to the original disease then to the plague on earth that followed. It’s knowing that if they falter, for even a moment, they will be destined to be like them: undead, with nothing left inside them but the urge to gnaw and rend.
“We need you here, Bakugou,” his deputy tries one last time.
Katsuki shoulders his pack. He isn’t taking any food with him. Every little bit is needed by the 5000 souls he’s leaving behind— all that they could find alive from a population of over 400,000.
“This place is as secure as we can make it. You already have the routine down: sleep, forage, sweep in the day; avoid loud noises; hole yourself in during the night.” Katsuki says the words more to reassure, and not because either of them needed reminding.
“You should at least take one of us with you. Someone to watch your back.”
Katsuki shakes his head. “It’s bad enough I’m going away. We can’t afford to leave the people here unprotected.” He claps a hand on her shoulder, forestalling further attempts to dissuade him. This is an old argument, and they’ve already rehashed all possible dialogue. “You have command.”
The new team leader nods, solemn. “I have command.”
Katsuki has already walked a ways down the path, the barricade closing behind him, when he hears the shout.
“I hope you find what you’re looking for, Bakugou!”
He doesn’t bother to look back. He knows he can only go forward. Katsuki goes down the mountain and begins his long, dangerous trek back to Tokyo.
Katsuki would never admit it but he hadn’t been certain they would survive that first night. The wave-upon-wave of animated corpses had stopped about an hour after dawn. The grey haze was still there, blocking the sun’s rays, but it was no longer dark of night.
It was an easy hypothesis to prove. They checked the streets and it was mostly empty of reanimated dead. Somewhere in their dead, infected brains, some survival instinct kicked in and they hid themselves away— ineffectively in most cases, unthinking, crushed tight under any possible cover, stepping on each other, hopelessly mangling their bodies in the process. Those that Katsuki and his team discovered, they dispatched without much resistance. By the time noon hit, any corpse they saw in the open was either truly dead or writhing in agony— something blasting, burning or exploding couldn’t make them do.
Those who still responded in their comms, all confirmed the same thing: the fuckers couldn’t stand the sun. It was the one bright point they’d found since the nightmare began.
They knew the grey haze didn’t reach far up in the sky, certainly not as high as the clouds. Katsuki had used his explosions to launch himself up the day before, back when all they had been worried about was the weird ass thing above their heads, and he’d seen clear blue skies once he cleared it.
So they planned to head up, to places above the grey haze where the sun still reigned. To a place they could barricade themselves in and defend at night. The good news was that almost 80% of Japan was mountainous. Hike up the nearest mountain and hole up. A quick check of the map told them there was a hospital compound that they could use up a nearby mountain.
What worries Katsuki when he tries to sleep, what he stubbornly refuses to think about when he’s awake and listening for the approach of those who are supposed to be dead, is that Tokyo and its surrounding area is located entirely in the flatlands.
There’s been no contact from the capital for months now.
He first encounters survivors on his fourth day out. That isn’t unexpected. He and his team had worked in ever widening arcs and any survivors within that area would already have been in the mountain encampment.
“But I thought— I was h-hoping we could stay with you.” The man is husband and father to the woman and child standing beside him. All three look haunted; all three had cried for joy and relief when they first saw him. Katsuki’s uniform is battered, but he’s still recognizable as Japan’s top hero.
Katsuki shakes his head. “I’m heading back to Tokyo. And it’s too dangerous to bring you. It’s better you head to the safe zone up the mountain. Barricade yourself at night; stay on a higher floor, if you can. Stay quiet. Travel during the day. Bring all the food you can find to share.”
“I don’t understand. They say Tokyo was overrun.” That’s what the last the news had said before it all broke down. “W-why go at all?”
“There’s something I need there,” Katsuki says quietly.
“It’s that important?” the man asks over the sound of his wife crying, holding their young daughter close.
More important than his duties as a pro hero, than keeping a helpless family safe? is what he’s really asking, and it’s what Katsuki hears loud and clear.
“Yes.”
Katsuki doesn’t sleep during the night anymore. He can’t afford to. He’s always on alert from dusk until dawn, already holed up in his pre-scouted safe area even before the sun he cannot see dips down the horizon. It’s a balancing act— to barricade himself in a place he can defend alone if breached, but not be trapped with his back to the wall if overrun.
He sleeps on open rooftops when his watch tells him the sun is high in the sky and danger is at its lowest. His sleep is rarely peaceful. Even before this endless nightmare blanketed the world, Katsuki has had his share of horrors: has seen good friends fall in battle; has tried to keep pressure on wounds that wouldn’t stop bleeding; has screamed and begged for listless eyes to stay on him, and watched the light in them go out.
But this dream isn’t like that. It’s a rare good one.
“Watch your six, Deku!” he shouts irritably even as he blasts the two-bit criminal away.
He hears laughter, as bright as the morning sun and just as warm.
“Why do I have to do that, Kacchan? I know you have my back.”
Katsuki wakes up and wishes he hadn’t, desperately clinging to the fading wisps for as long as he can. He gives himself a few moments. There is no one to see him, no one to judge. He wipes the wet from his cheeks and gets up. He’s still a long way away from Tokyo.
He sees survivors here and there. He sees looting. Some violence. He sees hunger. Illness. Despair. He sees living, breathing people just trying to survive. He approaches most of them, helps where he can, updates his map with safe zones and survivor counts. He gives battle pointers and strategies.
He leaves instructions.
“Do not fucking wait for me. Run if you need to. Leave. Keep yourselves alive—that’s the main thing. But if I can, if at all possible, when I come back this way, I will look for you here,” he says grimly, pointing to a spot in the map— invariably in high altitude, strategically defensible.
They all ask him to stay with them. His answer is always the same. He understands the anger and disbelief, the pleading, the vitriol they hurl at him. Katsuki’s conviction never wavers: what he needs lies in Tokyo.
One time, there’s a boy, angry and afraid, hurting. “I wish hero Deku was here. Deku would’ve kept us safe!”
The boy is possibly 13 or 14. He would have grown up just as Deku was rising through the hero ranks. He would have worn his green hoodies and red shoes, and played with his action figures. He’s old enough to know, to remember, to have loved the former #1 pro hero. He would have cried with the rest of the nation when Deku fell two years ago.
The boy’s father clasps him closer in a protective gesture, suddenly anxious that Deku’s once-partner and main rival would be offended by his son’s words.
“I’m sorry, Dynamight-san. My son—”
“—is only telling the truth.” Katsuki looks at the boy and utters his own truth. “I wish Deku was here too.”
Katsuki had started out 4 hours away by Shinkansen, but the bullet trains are no longer running. He originally estimated it would take him a month to travel the 900 kilometers to get back home. He is the #1 pro hero— mere weeks ago, that meant something. He is strong; he is powerful. He just needs to be careful and not die.
But between encounters with both the dead and those trying to stay alive, it takes him nearly 4 months to reach Tokyo. Four long months during which he doesn’t know what he will find, but won’t allow himself to stop believing.
Katsuki holds one thought firm in his mind: salvation is in Tokyo.
And now he’s here. He had known the capital was overrun by the dead. But he never expected this.
The thing overhead is much thicker here. It shrouds the city wasteland in full midnight darkness, not the twilight Katsuki had gotten used to. The dead are moving; with moans and terrible groans, they crawl, lurch, and drag themselves out in the open even when Katsuki knows the sun is out overhead.
“Fuck!!” he whispers from his hiding place. Just to vent. Just to let the fear and frustration out a little. Not too loud that they’d hear him, see him, chase him again with insatiable, mindless hunger.
Katsuki is exhausted. He’s bone-deep tired from the battles he’s had to fight alone; the near-constant vigilance; the emotional and mental toll of having to live through this when so many others had not. Of needing to be selfish for once in his goddamned life and choosing what he needs first over everyone else begging for his help.
But now he’s almost where he needs to be. He just needs to run this final gauntlet.
It’s safer up on the rooftops. There will be less contact with the should-be-dead there. But there’s no way he can keep his movements quiet jumping from roof to roof: Explosion is a noisy quirk. They’ll follow him to whichever building he lands on.
And he can’t have that. He can’t lead them there.
'Kacchan’s amazing.'
The voice comes unbidden. Sometimes the voice is high and excited, a child urging him on. But the voice is deeper this time, still bright, but older. Softly teasing. Familiar despite the two-year silence.
'I know you can do it.'
He can do this. He is amazing. Deku’s told him so often enough.
Katsuki draws a deep breath and launches himself to the sky.
Katsuki stops on the roof of a building a full block away from his destination. He can hear them clamoring below, moaning for his flesh, all instinct and dead brains. They’re breaking doors and windows trying to get to him.
He aims a blast at a far off billboard sporting the face of a pro hero who once called him a friend. The explosion BOOMS and the metal creaks in agony as the structure collapses. The commotion halts the frenzied movements below. He fires off another shot— a different billboard farther down the street. More shuffling sounds as the dead reorient themselves. Another blast. And another.
Katsuki waits, heart pounding. He dares not look down— how they can detect movement when most of them have no usable eyes, he doesn’t know. But Katsuki knows how to wait for what matters.
When the sounds die down to occasional groans, Katsuki begins moving from building to building the hard way. Leaping, grappling, slipping and sliding using only his strength, agility, and conventional tools, trying to keep silent the entire time.
He reaches his destination nerve-wracking hours later. The building is all glass and stainless steel. There is nothing warm or homey about it. Everything was designed to project efficiency and clinical excellence. The Chiyo Institute had been at the forefront of biotechnology. Brilliant minds from all over the world came here to learn, discover, and push medical boundaries. There is no other place like it in the world, and Katsuki’s fucking lucky it even existed.
The displays are all blanked out and most of the overhead lights are off, but there is low illumination and some blinking indicators on wall panels, telling Katsuki the building’s emergency power is still on. Almost 6 months since the apocalypse and the power is still on. Katsuki’s chest clenches. The surge of relief is so raw his knees almost buckle under it.
It’s never easy, of course. The dead roam the halls. Some are trapped in rooms, growling and scratching at walls, without the awareness to open doors. This had been a medical research facility, once, and they would’ve brought some of the sick people here. People would’ve died too fast for help, reanimated, and infected the rest.
Katsuki is beyond tired but he knows where to go. He’s been here before. He bypasses the elevator bank— they won’t be running under emergency power anyway, and it would be too easy to get trapped there: the doors opening and a horde of undead waiting. Katsuki finds some of them shuffling around in the emergency stairwell but they’re easily dispatched.
There are more in the hallway when he exits at the right floor, and he makes enough noise disposing of the first two that the rest converge on him. But Katsuki hasn’t travelled all this way just to be taken down one hallway away from his goal.
He takes a deep breath after the last undead has been blasted away. The door before him is sealed. Unlit letters above it say CRYO-HIBERNATION. There is a print scanner and keypad, blinking and active, but Katsuki doesn’t have the proper prints nor does he know the code.
He explodes the door.
Inside is a cylindrical chamber with a full-glass cover, lying on its side. Two meters wide, three and a half meters long. It’s lit inside with a soft light, indicators blinking on the side panels. Katsuki stumbles towards it.
Izuku sleeps on, unaware of his presence.
“Deku, you fucker,” he exhales with a half-sob. He bends over the cold chamber, spreading his hands on the glass. He looks his fill, taking in the green curls, too long around his pale, freckled face. Izuku’s chest lifts up and down in slow, rhythmic breaths.
Katsuki hadn’t been sure. He had no way of knowing. The undead could have broken through. The emergency power could have failed. He could have come here and found Deku’s chamber torn open or Deku asphyxiated as his oxygen system failed.
He slides down to the floor, forehead pressed to the cold glass. With no one to see him, Katsuki weeps.
Two years ago, Katsuki had grasped at straws and consented to placing his husband under this experimental treatment. He hadn’t been ready to let go, and instead put his faith in bio-science he didn’t fully understand. Izuku’s body was too broken, and they put him in a long, deep sleep to heal.
But the world needs Deku now. And fuck knows Katsuki does too.
He takes a deep breath. “Time to wake up, sleeping beauty. The world’s gone to shit, and I need you with me.”
Katsuki takes a chance and presses an obvious green button. Mechanisms whirl inside, gasses swirl around the chamber, and finally, the glass cover slides open with a hiss. But it doesn’t happen like it does in the movies.
Izuku’s eyes remain closed.
Katsuki leans in for a kiss, Izuku’s lips cold against his. “C’mon, baby, wake up.” He slips his hand into Izuku’s cold one. His other hand cards through too-long green curls.
He didn’t know if Izuku would wake up. He had been in a coma even before he was placed inside this chamber. He was supposed to be under for twenty-four months. But then everything went to hell and it’s already four months past that. There is probably a medical protocol for this: waking up the almost-dead. But there’s no one left to ask.
Izuku’s skin is cold to the touch; he’s too, too cold. Katsuki keeps kissing him anyway, rough hands soothing freckled skin, urging him to wake up.
An hour and a host of threats and promises later, Izuku’s fingers, clasped in Katsuki’s, twitch. Soon but not soon enough, the green, green eyes open. They flicker and focus on Katsuki.
“Kacchan,” he rasps out.
Katsuki sniffs and barks out a laugh, wiping off his wet cheeks and snot with the back of his hand like a four year old.
“Yeah. Yeah, I’m here. Welcome back, Deku.”
“I feel like I’m in a sci-fi horror movie. Zombies and cryogenics.” Izuku’s walking around the room, flexing his arms, getting used to his body again. His muscles hadn’t atrophied despite the long medical sleep, but he feels wobbly and unsure.
“You weren’t just frozen.” Katsuki’s slumped down the floor, his back to the wall. “They were healing your body, too. Regeneration and stuff. You were in a bunch of medical journals.”
Izuku perks his head up in interest. He continues walking around, mumbling softly to himself. Katsuki is too worn out— body and soul— to smile, but a rush of fierce affection washes over him at the familiar sight.
“And the zombies? You think it’s deliberate?” he finally says, green eyes serious.
Katsuki shrugs. He’s had a long time to think about this. “There’s no fucking way it was random. They released the sun cover first, so the things could survive. And it’s much thicker in the big cities, like here in Tokyo. The way the disease spread— it was worldwide, all at once. No single patient zero. Natural epidemics don’t work that way.”
“But what for?”
Another shrug. “Maybe they weren’t expecting it to be this virulent. Maybe they had the cure but it didn’t fucking work. Maybe the fuckers are all dead and couldn’t stop the spread. Who knows at this point...” Katsuki trailed off. “It happened too fucking fast, Deku. Everyone was just gone. I was on videocon with the rest of them. We didn’t know jack shit at the time; we were just focused on giving assistance where needed. Fucking crowd control. Next day, everyone’s dead. They’re all dead.”
Izuku stops his pacing and kneels down in front of Katsuki. “I’m sorry I wasn’t awake.”
“I’m not,” Katsuki says immediately. “If you’d been awake, you would’ve been in that briefing with them, and you’d be dead too.” He pulls him in, and they mold their bodies together as close as they can, a tight tangle of torsos and clasping limbs. “I’ve never been so fucking thankful for anything in my life.”
“What do we do now?” Izuku murmurs close to his ear, running soothing touches up and down his back.
“I’ve seen survivors. There are safe camps. If we can organize, kill as many of them as possible, maybe we can shut this thing down.”
“Win and save, then?”
“Fuck yeah.”
Katsuki’s smile is a little grim, no longer as bright nor as fierce as his old one. Deku kisses him anyway.
“You know, we should clear out the building at least.”
Katsuki looks at him. “Why?”
“We’re gonna be clearing out the world, might as well start here. I need the practice anyway.” Izuku flashes a cheeky grin.
“What you need is clothes. You can’t go saving the world in a hospital gown.” Izuku laughs at that, the sound untainted by the harsh realities of the apocalypse Katsuki has had to live through. He finds himself vowing to protect it, as much as he can.
“There’s bound to be a locker room here somewhere. We need food, too, Kacchan. Supplies. We can look for the commissary, maybe raid the clinic? Kill a bunch of zombies along the way. You said they’re not difficult to kill, right?”
Katsuki shakes his head. He won’t be able to explain it properly anyway: Izuku needs to see it for himself. But this way, he’ll have Katsuki by his side. “Just go for headshots. They won’t dodge. Target the brains. And for the love of all that’s fucking good, don’t let them fucking near you.”
The hallway is littered with unmoving bodies when they step out of the cryo-lab. Izuku frowns down at the exploded remains but stays clear of them.
They go through the floors one by one. Deku is correct about the locker rooms. They find a bunch of lab coats and some street clothes that fit well enough, if a bit tight against Izuku’s too-broad chest.
Katsuki opens one locker and stares. “Oi, Deku. C’mere.”
Izuku obediently trots over and peeks in. There’s a pair of high-cut, red sneakers: pro hero Deku signature edition. They fit. Izuku beams, and Katsuki allows himself to forget for a while, basking in his husband’s nerdy, longed-missed presence.
They move on, keeping quiet, methodically opening doors and entering rooms as they pass. They hear a sound and Izuku whips around, alert. But something’s not right. It’s too quiet.
“Anyone here?” Katsuki asks. Not too loud, but firm, in command of the situation, as if he’s a hero again.
There’s a long pause.
“This is heroes Deku and Dynamight,” Izuku says, making Katsuki inwardly wince. He can hardly call himself that now. “Is there—”
There are audible gasps. There’s a scramble, and soon a scraggly-looking group of people have come out of hiding.
There’s a babble of words.
“Hero Deku!”
“You’re awake!”
“We’ve been trapped here.”
“Thank you for saving us!”
“The canteen’s almost run out of food.”
“Thank you!”
“We didn’t know what to do.”
“Thank you so much.”
Deku’s smile is just like it had been before. “It’s alright now. We are here.”
It ends the same way. People crying, begging, asking for things Katsuki cannot give.
“Haa? Aren’t you listening? It’s not fucking safe! We’re clearing out the building. Stay here and we’ll come back for you later.”
“Please,” one of them sobs out, adding to Katsuki’s guilt and shame.
He feels Izuku’s fingers on his wrist. “They’ve been through so much, Kacchan. They need more than just safety right now.”
And isn’t that the truth, Katsuki thinks, relaxing at Izuku’s touch. Sometimes, you would brave death to be with someone who makes you feel safe, who can cure all your ills.
“Fine,” he says, without his usual bite. He turns to the survivors. “But stay behind us at all times. Do not try to help. If you get fucking bitten, I will end you. Even bright-eyed Deku here can’t save you.”
They move to the next floor down with their rag-tag group in tow, Katsuki leading the way. Everyone knows to be silent. They all freeze when they hear the moan.
“Is that— is that them?” Izuku’s body is coiled tight with tension. The fine hairs on his arms are standing on end.
“You’ll know when they’re near. They’re never quiet,” Katsuki answers, voice low, hardly above a whisper, “but they get louder when they sense you’re there. And that brings more of them.”
Deku nods, obviously unnerved by the sounds.
A sign on the wall identifies the next floor down as a hospital ward. Izuku pushes open the door and he gets his first look at the undead. They fill the hallway. There are more moans coming from the rooms on either side of the hall. They’re in scrubs, in white coats, in hospital gowns, much like what Izuku had been wearing a few hours ago. After 6 months, they barely look human anymore.
Izuku and Katsuki step out anyway, going into battle stance. It’s what they’re here for, after all. The ones closest to them sense the movement, and their moans ratchet up, calling for others like them.
Katsuki can see familiar green lightning from the corner of his eyes, glowing up and down Izuku’s body. Alone, Katsuki would not have chosen to do this— to deliberately provoke an encounter— and the undead number enough that they could get lucky and overwhelm even him.
But he has Izuku by his side, and that makes all the difference.
“Remember, nerd, aim for the head.”
When they were still young and relatively unknown, people thought Izuku was a close-combat specialist. And he is. His kicks are deadly. But what villains had soon learned is that his ranged attacks are deadlier.
With a flick of his One For All-powered fingers, Izuku sends wind pressure towards the undead. He’s developed precise control over the years, and the wind damage runs like eight perfect scythes down the length of the hallway. Heads topple from chins and shoulders, followed closely by bodies, dropping like marionettes with their strings cut.
Katsuki blinks. Torn between being proud, envious at how easily Izuku did that, and turned on, all at once. He’d forgotten how hot Izuku makes him feel when he fights for real. He settles for laughing, loud and free— something he hasn’t done since his personal nightmare began: since Izuku began his long sleep.
More undead come out from the rooms, and Katsuki moves. After all, he can’t let Izuku have all the fun.
They go up to the helipad deck the next morning. They sealed off the lowest floors last night so even if the undead enter from the outside, they can’t go up and swarm the building again.
The facility’s survivors go up with them. They huddle together, buffeted by the strong winds. Seeing Izuku and Katsuki fight yesterday seems to have calmed them down, brought them courage, and they’re now willing to stay behind so the two heroes can scout the area.
Izuku looks up at the midnight-dark sky. He shivers lightly. It’s cold without the sun.
He walks to the edge of the building and surveys the city. Katsuki steps up beside him. There are undead below them, slow moving, visible even in the darkness.
This city used to be under their protection. It’s time they take it back.
“Go for it, Deku.”
Green lightning covers him. He leans into a familiar stance, pivots his body, and flings his leg out in a shoot-style wind attack. The controlled scythes from yesterday are nothing to this. The pressure blows a swathe through the midnight haze, clearing a section a hundred meters wide and even more in length.
Sunlight, pure and bright, comes pouring in. Agonized moans rise from below as counterpoint.
Katsuki closes his eyes and lifts his face up to the open sky. “I knew there’s a reason I came back for you.”
“‘Cause you love me?” Izuku’s voice is just as he remembered it: bright, softly teasing.
He smiles. “That, too.”