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Zero: The Birth of the World's Best Hero Duo

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“So you’re in your third year, now, which means you need to start thinking about your future seriously. I’m going to pass out some forms for you to fill out with your interests and top high school choices.”

Katsuki lounged in his chair, feet up on his desk and head resting on Deku’s desk behind him. Like anyone needed this shit. Every loser was going to try for the same fucking schools, and they already knew it. You either knew or you didn’t, and if you didn’t you were a dumbass and would probably have Their dumbass teacher knew the sheets were fucking worthless too--the man looked bored as hell. “Of course, I know everyone wants to be a hero, but try to be realistic about your choices in schools.”

The students cheered around them, all whispering excitedly. “Shitty extras.” He opened one eye to glare at them. “Don’t you all know you don’t have what it takes to be heroes?”

“Kacchan!” Deku tugged at his collar. “You shouldn’t call people extras! That’s mean!”

Katsuki snorted. Deku never liked it when he did that, but… “the sooner they realize their place in the world, the better.” He was doing them a service by helping them realize they weren’t cut out for it. “Deku and I are going to UA and we’re going to make it big as heroes, unlike the rest of you losers. You’ll be lucky to be sidekicks to some D-list heores. We’ll be unbeatable.”

“Deku?!” A bunch of giggles burst out across the classroom and Deku slumped in his seat. Log Head spoke up, “Your quirk is awesome, Bakugou, but Deku’s quirkless! He could never be a hero. If anyone doesn’t have what it takes, it’s him.”

“Huh?!” Katsuki stood up, his chair slamming to the floor as he stalked toward his classmate, small pops flashing from his hands. “You wanna say that again, you fucktard? Deku could beat any one of you in a fight, quirk or no quirk!”

“Kacchan!” Deku’s hand closed around his wrist. “I appreciate the support, really, but I’m not about to go fighting anyone for no reason…”

“Tch.” Katsuki looked back at his soulmate. Despite his clear muscles, with an attitude like his it was no surprise the dumbasses all thought he lied about his blackbelt. “Whatever. It’s not like you need to prove yourself to these lameass weaklings. You’ll get into UA, and that’ll speak for itself.” He walked back to the chair and slumped into his seat.

Fucking extras. He couldn’t wait to get out of this dump.

Of course, since Katsuki wanted the day to go by quickly, it was the damn slowest day ever. By the time school let out, Katsuki wanted to scream.

All day the shitty extras has been snickering about Deku and how he could never be a hero, and Katsuki hated the way Deku’s shoulders had started to get lower and lower.

“You know they’re fucking dumbasses, right? They don’t know shit.” He leaned against the locker while Deku put his shoes on to leave.

“I know, Kacchan. It’s just…” Deku sighed, stranding up and adjusting the strap of his backpack. “It’s hard not to listen, some days.”

“Tch.” Katsuki started walking, knowing that Deku would follow. “They don’t fucking matter. The only ones that matter are the ones that take the time to know you, and we all think you’re fucking awesome.”

“You’re right, Kacchan. You always are.”

“Hell yeah, I am. So stop moping, you shitty nerd.”

“I’ll try, Kacchan.”

“You fucking better.” Katsuki rolled his eyes at the nerd but was content to keep walking in silence as long as his soulmate wasn’t moping.


Katsuki’s head whipped toward his soulmate’s voice. What the fuck?! Why was his voice scared? Deku was a few steps back, pointing at the ground where… sludge was wrapped around his foot? Deku was trying to yank it free, but the sludge kept clinging to him.

Katsuki charged forward and held an exploding palm against the sludge. The second it recoiled he threw Deku behind him, earning a shout of distress and annoyance from his soulmate.

Obviously, strength alone wouldn’t work against this…. Thing. This thing that was quickly forming into a towering figure, laughing at them. “What a strong quirk! You’ll be a great choice for my next invisible skin!”

What fucking kind of messed up shit was this guy on?!

Katsuki didn’t even have a second to think before he was surrounded in the sludge. His palms exploded immediately, but the thing wasn’t reacting. He kept it up, though, hoping that maybe a constant barrage would do something.

It was cold, so cold. And he couldn’t move. Couldn’t breathe.

He dimly heard Deku yelling his name, screaming.

Sludge was flying everywhere. Sludge on fire.

Deku was in front of him, clawing at the villain. Katsuki gasped as his mouth was freed, “Get back, Deku! The last thing we need is both of us captured!”

Deku was crying, shaking his head frantically. “I have to help you, Kacchan!”

Damn it! Stubborn dumbass! Couldn't he tell that strength alone wouldn't work against this guy! “Use your fucking head, idiot!”

Deku blinked, but actually scrambled backwards at that. Katsuki gagged as the villain once more forced itself down his throat. He couldn’t breathe. He couldn’t… his palms lit up.

“Kacchan, stop!” Stop? Stop what? He couldn’t… stop! He had to fight! But it wasn’t… it wasn’t doing anything. But he had to try! He clenched his eyes shut in frustration. “You’re setting the park on fire, Kacchan!”


That… that wasn’t good. Shit. Tears formed at his eyes. The sludge was everywhere. It was inside him. He couldn’t…

Suddenly the sludge stopped.

Katsuki opened his eyes. Deku. Deku was throwing things. Throwing them at the villain’s eyes. The eyes weren’t sludge! If he could just get an arm free…his right arm could probably reach.

He struggled. He lit his palms on fire a few times, trying to startle the villain into releasing him. Hopefully the park would be ok. The occasional blasts were working a little bit better since the villain wasn’t constantly bracing against them.

Deku was there again, clawing at the sludge by his arm, fighting against it, digging into it.

Katsuki gagged, eyes bulging as the villain surged deeper into his throat. He could feel it attaching to his skin, to his face. It stung, it stung like a thousand needles poking into his skin.

Don’t focus on the pain.

Focus on his arm. On Deku. On his soulmate. On getting free.

Deku’s finger looped around his, a solid presence amidst the sludge, and his soulmate yanked. He yanked and yanked and Katsuki could swear his finger broke but he didn’t fucking care and---


He could feel air.

His hand was free.

Deku grabbed his wrist and yanked it upward, jerking it through the sludge and resistance. He pulled and pulled at Katsuki’s hand, but kept his own hand clear of Katsuki’s blasting range. Katsuki quickly let loose an explosion, using the force to propel his hand upward as Deku pulled.

The villain hissed, pushing more sludge down Katsuki’s throat. “Shit. He found me.”

What did the villain mean by found him? Who?

He couldn’t care.

Don’t focus on the pain.

Don’t focus on it.

“Now, Kacchan!”



Katsuki could feel his wrist break from the awkward angle and the force of the recoil.

But the villain was shrieking. Retreating.

He could feel the slime pulling out, shrinking as it began to run away.

Katsuki fell to his hands and knees, gasping.

Deku was right next to him, calling his name, his hand on his shoulder. Katsuki tried to focus on its warmth.

He needed to focus on Deku’s warmth, not the coldness from the sludge.

Katsuki heaved, trying to throw up. Trying, but failing. He could still feel the slime. Could still feel….

He heaved again.

Deku’s hand was tighter, now. His voice more urgent.

Katsuki wanted to answer it, wanted to calm the shitty nerd down, but he couldn’t—couldn’t speak. The sludge--

Katsuki collapsed on the ground. He tried to breathe deeply, tried, but it was like the sludge was still there.

He reached up, trying to claw at his throat, but warm hands pulled him back.

Katsuki thrashed against tightness around him, against the tightness in his throat.

The sludge, was it back?

He couldn’t move. Panic crawled across his skin.

He couldn’t breathe.

Couldn’t save himself.

Couldn’t save Deku.