Katsuki gets to his feet. The anxiety that took root in his stomach is worse than ever. If the villain gets to Izuku—he doesn't want to think about that. Izuku will someday be strong, but isn't yet. Izuku will someday know how to defend himself, but hasn't learned yet. Izuku is alone, and it's Katsuki's fault.
"We have to go!" He calls to All Might, who's still staring at the spot where the villain disappeared.
Katsuki runs to the alley's exit without looking back. As long as Izuku is safe, it doesn't matter what else happens. He skids to a halt when he sees Izuku's green hair and yellow backpack. Izuku is walking back from school like he would any other day. Izuku who hasn't met All Might, who has no hope of getting a quirk. (It feels wrong, so wrong). He sticks to Izuku's side like glue, and they head for home.
A lack of conversation stretches between them. Katsuki is thankful that Izuku doesn't ask questions. Glancing down, he notices that the collar of his school uniform is off kilter. At least the sludge didn't leave any residue behind. He tugs on the end of his sleeves and straightens out his jacket. His ears buzz with silence.
It's an awkward silence, but the absence of sound becomes wrong. The hair raises on the back of his neck. The feeling lasts for a second. One second, and Katsuki knows what's going to happen next. Feels it. Sees it. It's not what happened last time, but the circumstances have changed. Sludge bubbles out of a nearby manhole. Muddy, sinister, but quick. Katsuki's reactions are nowhere near as fast as they someday will be, but they are fast enough to push Izuku out of the way.
He hears Izuku scream his name as the cold sludge crawls over his body and entangles him again. He knows what's coming. The cold. The lack of air. And that almost makes it worse. His eyes linger on Izuku's face even as the villain carries him away. His heart pounds loud in his ear, louder as the oxygen drains from his blood and his lungs strain for the air they are deprived of. No amount of struggling can loose the hold the sludge has. Explosions rip from his palms, and his vision fills with orange flames and the blacks and grays of ash. His eyes sting with the effort of staying open, and the world goes in and out of focus.
Somewhere in front of him, he can see a face framed by green curls. His ears pick up the sound of Izuku yelling his name, but the syllables sound distant, like he's shouting from far, far away. Izuku moves just close enough that Katsuki can see the blurry outlines of his features. With sludge suffocating him, he has no way to tell Izuku not to worry. But it's too late. In a sea of explosions and swirling colors, Izuku's face seems like the only thing that's clear. His eyes flutter, and blackness invades his field of view from the periphery. But even as he loses consciousness, he knows he'll never forget the look of torture in his best friend's eyes.
His last thought before his mind turns cold is that there must be pro heroes around somewhere and, at the very least, he pushed Izuku out of the way. The dark cloud of unconsciousness takes over, without him being aware of giving up control.
Izuku's screams are something he never wanted to hear. Not with this much clarity. Not piercing his ears as much as it pierces his soul. Not like he's there again.
The agony of injuries from the other life aches in every cell of his body. His stomach clenches, and nausea begins to climb his throat. He hears the throbbing echoes of battle cries in his skull and flinches from the thrumming pain in his sides. His mouth is dry, but the taste of ash and blood coats his tongue. A cough forces its way from his throat, and he remembers the bitterness of spitting up blood from broken ribs tearing into his chest.
Scenes of the past swim across his vision. Soul-deep fatigue echoes through the years. How long has he been fighting for? Decades? Years? Days? Or has the fight even begun?
Izuku's face flashes by in smiles that grow scarce. There are tears and shouting and too many disagreements about whether to save the civilians in front of them or send their forces to pursue villains. They'll save more people in the long run. But no hero should be able to turn their back on a crying child, and their cries echo from every corner. There aren't enough parents left.
Not enough pro heroes either.
Students run themselves ragged trying to fill the gaps that the pros have left, but the villains are merciless. Cruel. But strongly principled in their own twisted ways. And people agreed with them. Not enough to forgive their violence, but enough to shut their doors and watch from their windows instead of try to fight.
Katsuki remembers running out. Of energy. Of patience. Of friends.
There's something that sounds like Kacchan, I always— and blinding pain before his mind goes blank.
Resurfacing to the present is a shock. It feels like he's been freefalling through memories, and he just hit the cement below. His mind takes a moment to orient. The sun on his face feels foreign, and he doesn't know how to open his eyes and pretend he didn't just remember a past life. Especially when all he can feel is brokenness. And all he can hear is a voice raw with pain.
Katsuki blinks his eyes open. The bright blue sky above and the pro heroes huddled around him belong to someone else. He feels disconnected. And there's Izuku. Izuku who, he realizes, is kneeling over him, face closer than it has any right to be. Light freckles dot the bridge of Izuku's nose and spread out over his cheeks. They pale in comparison to the darker ones, and Katsuki wonders why he never noticed them before.
Hi blinks again. His thoughts feel like their running in slow motion. The memories are still floating behind his eyes, but most of the pain ebbs out of his system—all ghosts of injuries from the other life. He notices that the sludge villain is gone and taken care of. Physically, Katsuki is fine, a sore throat and a couple of bruises are nothing, but mentally? Mentally, the weight of his memories has the same impact as being hit by a bus. Or several.
The team of medics fuss over him for a while, before he's finally allowed to get up and walk home with an oddly quiet Izuku. No one tells him what happened. He sees the dirt smudged across Izuku's face and the disheveled state of his uniform. His eyes fall on the extensive bandages around Izuku's right arm, and, suddenly, he gets the feeling that he doesn't want to know.
A year later finds Katsuki sitting in the auditorium for UA's entrance exam, and Izuku nowhere in sight. Glancing around the packed seats, he sees people that he knows and doesn't. The seat next to him is filled by some unknown idiot. (Izuku was supposed to sit there, he knows this now). Katsuki grits his teeth and aces the exam. He gets 77 villain points and 13 rescue points. It's apparently some sort of record.
He tries to feel happy when his acceptance letter arrives in the mail. Izuku doesn't talk about high school, and Katsuki doesn't mention UA.
The first day of class comes and he slouches into the 1-A classroom and sticks his feet on the desk. Iida yelling at him for it is almost nostalgic. There are 20 kids in class 1-A, and Katsuki hates staring at the chair that should be Izuku's.