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The Defect

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Todoroki’s declaration sends his blood boiling.

Seething, he watches as the half and half bastard challenges the idiot nerd -and worse of all, the dumbass reciprocates. What the fuck? Why Deku of all people, a one trick pony who broke his bones every time he used his Quirk?!

Why not-

The snarl he lets out is predatory. He’s out of his seat before Kirishima can hold him back. Stalking up to the dual haired brat, completely ignoring Deku’s squeak of fear as he barges past him.

“The fuck are you thinking giving Deku a declaration of war, you shitstain!?” He’s right up into Todoroki’s face, but ever the blank faced motherfucker just stares at him unblinkingly. Uncaring. “Him, really? He can’t even use his Quirk without ending up in the infirmary, the shitstain will be out by the first round!”

Like Katsuki was nowhere near enough of a threat to bother with.

(It makes the hair at the back of his neck rise up.

He’d seen that look before, long ago. The disinterest.)

The silence stretches across the room. The rest of the students are watching -waiting. Gauging their reactions. Probably chuckling internally at how well the Icyhot bastard was handling the class bully.

It makes his blood roar with rolling, unwavering violence.

(Mitsuki always said he got that poison from the old man.)

Kirishima comes to wrangle him back. Hand on his shoulder, hesitant but determined, Kaminari hovering nervously at his side. They say something, but he tunes out their attempt at calming him down in favour of glaring at the two idiots in front of him.

Deku looks determined, but then their eyes meet again and he looks like he’s swallowed a lemon, wavering courage falling apart like a castle of cards.



Todoroki’s nonplussed by his threats. Unruffled as ever. There’s a gleam in his eyes, a quiet, vindictive determination Katsuki finds familiar -he sees it every morning in the mirror- but it's contained, directed more guarded.

It makes his blood burn .

Katsuki glares until Aizawa comes to fetch the class, takes one look at the commotion, and barks at them to get to the arena under the threat of expulsion.







“Hey old hag, where’s my dad?”

A sharp smack is delivered to the back of his head, nearly bowling him over had he not braced for it against the kitchen counter.

“Don’t speak to me that way, you brat!” Mitsuki hisses as she fetches the condiments from the spice rack. “Why are you even asking?”

“Cuz’ I want to, duh?”

Another smack.


Mitsuki’s nostrils flare. The look in her eyes is dark and guarded.

“You’ll meet him someday, kid. When he wants you to.”






“I just want to say….I’m gonna win.”

There’s pandemonium.

The crowd roars with laughter as the students rise up with a unified bellow. Katsuki stares them down through a impassive mask that didn’t betray the burning excitement roaring in his veins.

Deku’s the only one that stands his ground as he walks back into the crowd of students. Katsuki shoulders him aside when he strides through. Hands tucked in his pockets, he watches as the other first years scramble out of his way.

He ignores the weight of Deku’s eyes on his back.

(There’s a shudder travelling down his spine that he’s barely able to restrain and at that moment, Katsuki knows, just knows , that he is watching.)








There’s a titan looming over him, fire burning in icy blue eyes. Katsuki watches him curiously, barely feeling the tight grip of his mother’s hand on his shoulder. Her manicured nails are digging slightly into his flesh, but he barely registers it.

“Introduce yourself, boy.” Mitsuki says, sickly sweet and pleasant. Then, under her breath and more sharply, she hisses, grip tightening nearly to the point of hurt. “Don’t slouch. Behave.”

Katsuki’s legs quake, but he stands his ground. He tilts his chin up, squares his tiny shoulders, and looks at the man straight in the eyes. For a three year old going on four, he doesn’t flinch under the weight of his stare.

“Hello, sir. My name is Katsuki.”

The man stares at him for a moment, taking in his firm introduction and unwavering stare.

Then he grins.

It’s not a nice smile; it’s sharp and predatory. Expecting.

It takes all but a fraction of a second for Katsuki to return it.






Todoroki isn't giving him the time of day.

High in the sky, Katsuki glares at his back. The younger boy was still ahead, but the distance between them was getting shorter and shorter.

His opportunity comes when the minefield section rolls over.

Todoroki slows then, carefully stepping around the loaded mines as fast as he could. With the finish line so close and his hands starting to cramp, Katsuki joins him on the ground. Running up to his side, snarling as the half and half boy sends a small blast of ice his way as he nearly passes him. Well, Katsuki might have tried exploding him first, but that was just a detail.

In response, Katsuki ducks under his swing and brutally elbows him on the side.

The choked sound Todoroki makes is music to his ears. The taller boy stumbles, faltering at the sudden lack of air in his lungs. Taking the opportunity, the explosive blond leaps over a mine and accelerates, heading for the finish line.

Unfortunately, just as Katsuki has victory in his grasp-

Fucking Deku promptly barges in with all the grace of a bull in a china shop.







“When can I start?”

“When your Quirk manifests. Only then you will start down the path to becoming a hero, boy.”






He can still win this.

He can still fucking win this.

Deku somehow had stolen the first spot from him, but mark his words, Katsuki was going to stela it right back and bash the nerd’s face in while he was at it, because if Katsuki was anything it was a overachiever.

But for now, he has to get a team ready for the second half of the tournament.

Which is a bit hard when he barely paid any attention to his classmates during the first semester. They’re crowding around him, students from his own class and other clambering for him to pick them. All Katsuki hears is the pounding of his own heart in his ears and a burst of frustration when Horns shrieks at the realization he barely even knows some of their names.

Give him a fucking break, it’s not like its been a full semester yet. Besides, why the fuck should he care about people he doesn’t even talk to? He barely knows a handful of their names; that’s enough in Katsuki’s opinion.

Mina Ashido apparently disagrees, if the way she forces herself into his team with a upturned nose and a indignant huff has anything to do with it. Katsuki’s not sure where Shitty Hair -Kirishima- comes from, but he pushes through the crowd gathered around Bakugo begging for attention and looks him straight in the eyes, unwavering.

Just for that, Bakugo listens.

That doesn’t mean he likes what he hears.

“I asked Todoroki, but he already has a full team. So come on, can I join?”

Bakugo has to momentarily count backwards from ten to zero to keep himself from bodily tossing the redhead into the stands with an explosion. He’s useful, he thinks as Kirishima continues to argue his case, showing off his Quirk as he did so.

He doesn’t know. I can’t hold it against him.

Then Kirishima mentions Deku and the ten million ribbon and the only thing Bakugo can do is bite.






They meet, again and again.

Katsuki learns that the fire does not burn him -could not burn him- and every few weeks when he sits on the couch next to his goliath of a father, he can bask in it’s warmth as he talks about how he laid another classmate low or pushed Deku around, or fought a boy a grade higher than him for looking at him wrong and won, even without his Quirk.

At this tale of violence, his father does nothing like his mother. He does not shrug his shoulders and ignore him, does not chastise him for cutting into her work time. Instead, his father smirks and lays a hand on his head. It’s warm and cozy against his hair.

“Good, good. You’ve shown them their place.” The look in his eyes is proud. “Under your feet -and you, at the top.”

Katsuki preens.

The next time he crosses path with the boy from the higher grade, he taunts him and then fights again, just so he can regail his father with another tale of conquest and feel the basking warmth of a hand on the top of his head -the first time anyone had touched him so comfortingly.

He does it again and again, his teachers’ scoldings and Deku’s cries only a background noise compared to a touch that was so drastically different than Mitsuki’s sharp nails and cutting words.

Violence is in your blood, his father tells him one time when he comes home, knuckles bloody. You’re meant for the top, boy.

Caught in his gravitational pull, Katsuki believes his every word with all the fibers of his being.








They pass, if not barely.

His first match is against Round Face, the girl with the gravity Quirk that trailed after Deku like a lost puppy. She looks ridiculously out of place as she comes to stand in front of him in the middle of the arena. For a moment, Katsuki expect her to just turn around and run back into-

Round Face plants her feet and stares him right in the eyes.

Well, there was that.

In the end, Uraraka’s utterly batshit strategy does not work -the insane bitch could have killed them both and some of the audience- and he watches as the nurse staff wheel her out of the arena on a stretcher. His classmates jeer at him for hurting such a girl but honestly, what were they expecting?

They were here to win and become heroes, not to fuck around.

At least Uraraka got with the fucking program.






“....then you’ll take me home?”

“That’s right, Katsuki. Then you’ll come home.”







“And now from the hero course, the son of Endeavor, Todoroki Shouto!”

The crowd cheers. Katsuki has to bite his lip to force down the wave of humiliation clogging his throat. He focuses instead on giving his opponent a sharp, predatory grin that Todoroki answers with his ever blank mask.

“Versus his beast of a classmate, Bakugo Katsuki!”

Amongst the cheering, there’s more than one boo. Katsuki shoulders through it, using the screams and jeers to fuel his rage.

This was his fucking moment, he was going to have the lot of them gaping by the end of this match. After this, they’d know who was the strongest.

Who was the best.

(Who had the better Quirk.)

Right away, Todoroki tries encasing him with ice. Katsuki was having none of that shit, and he tears through the glacier with his explosions.

He’s not here to play with fucking snow.

He wants the flames, bright hot and sparkling, their brilliance and warmth enough to be felt from several feet away.

He wants Hellflame .

Which Todoroki refuses to give him. He pushes and pushes and still, Todoroki ignores him, gaze clouded and unsure as he sends waves of frost at Katsuki, who roars and kicks and curses, the filth spewing out of his mouth enough to make a sailor blush.

Despite this, Todoroki is unflappable as ever.

Stoically keeping him away with his ice, unperturbed by Katsuki’s demands.

Like he doesn’t matter.

Like he isn’t even worth the time to respond.

Katsuki’s heart beats like a drum in his ears. He can’t fail now, not when he was so close. Goddamn it the fucking popsicle had to use his goddamn flames otherwise Katsuki was going to kill him!

Am I not even worth that?!

Then Deku shouts from the stands and suddenly Todoroki is alight with fire -fire that is warm and bright and familiar. Katsuki turns giddy at the sight, excitement lighting up his veins -even the fact that Deku is the one that brings the flames out, again, is ignored as he leaps into the sky. Twisting in midair, Katsuki begins going through the motions of a special attack he’d been working on for months, long before he ever came to Yuuei.

Howitzer Impact.

Standing in the eye of this miniature tornado would be dizzying but for Katsuki, he only feels exhilaration at the thought finally, fucking finally doing what he’d been dreaming to do for years -to show the old man that he could shove his Quirk up his own ass, that Katsuki was brighter and better than any fire Hellflame could produce.

Now now now-

But then Todoroki lowers his arm and looks down, flames dying away to wisps of smoke -and Katsuk’s plan, his dream, withers and dies once more by the hands of a Todoroki.

Later, as Midnight puts him to sleep, the last thing Katsuki thinks is that this was a hollow victory and the whole world was there to see it.








Bright popping heat and sparks emitted from his palms as he held his hands up, smile blinding and ferocious. It hurts, but Katsuki pushes through it with a burst of adrenaline and excitement.

“Look! I did it, dad, I did it!”

From the corner of his eyes, he can see his mother in the adjoined kitchen, expensive manicured fingernails tapping against the stone counter. The placid, perfect smile is gone from her lipstick red lips, replaced by a small frown.

His father is also quiet.

Katsuki wavers.


There's no response. His father shifts away, expression closing -locking him out. Katsuki watches him stand up, confused at the sudden change. He doesn't understand. Why isn't his father happy, wasn't this what he wanted? What he had been looking for?

What did he do wrong? He worked so hard to make his Quirk appear early, he'd done everything right, why wasn't his father proud?

How could Katsuki fix this?

“That's not Hellflame, Katsuki.”









Later, when he’s chained to the stadium under the crowd’s roaring cheer, Katsuki likes to think he’s giving the bastard second hand humiliation.

He fucking hopes so, because he's definitely feeling it, more so than the metal digging into his wrists and the muzzle keeping him from screaming obscenities. Every twist and push he makes to break out only makes the crowd holler louder, mocking him with their laughs and jeers and his throat tight. Fuck, the bastards are enjoying this.

(He has to wonder how Yuuei obtained these things in such a short notice.)

Something prickles at the corner of his eyes, but he fights it back with all of his might -the humiliation at being bound and restrained like a animal burns , but crying on top of it would incinerate him.

When All Might descends from the sky and holds up a medal for him, Katsuki balks. Like hell he was accepting it -even if it wasn't a empty victory, like hell he was taking that piece of shit while bound and gagged like a fucking rabid animal. He wasn’t going to accept some shitty participation prize, not when the real winner was standing to his right.

Just the reminder makes his blood boil even further.

Unfortunately, Todoroki is too busy staring down at at the ground to notice his baleful glare.

It's fine.

Fucking fine.

Katsuki is used to being ignored.






When a fourth week passes by and still, no looming giant stepped through the doorstep. No man waited for him in the dinning room after school, bulging arms crossed over his chest as he listened to Katsuki brashly explain how he beat children one or two years older than himself.

There's nothing but silence.

And Mitsuki.

“You just had to inherit my Quirk.” She’d muttered as a passing comment one day as she walked by him, phone held up to dial. “Had to break our agreement.”

Katsuki feels tiny and insignificant when she turns her bright, scarlet red eyes down at him, her perfect dark lashes falling over that disdainful glare.

“Now I'm stuck with you.”

She pushes past him, heading for her bedroom.

Katsuki lets her go; his mother -Mitsuki- had never been one for affection. The most he ever got from her were sharp fingers digging into his back so he would stand straight, brisk shushing when she was one the phone, and complains when he returned home with clothes covered with dirt. Barked reprimands when he didn't finish his food quick enough, or did things to her liking.

He doesn't remember a time where she'd given him anything else.

He does, however, remember a too big hand on his head and a sharp, roguish smirk mirroring his own, toothy and razor sharp. A short, proud, low chuckle when Katsuki was just a bit too loud, a bit too brash, a bit too much like-

His feet carry him to the large window by the front door.

Katsuki sinks against the windowsill, arms crossed under his chin as he watches out the road. Pointlessly hoping to see that sleek back car roll up in front of their house.

Nothing happens the longer he stays there, curled up against the window. The summer sun was bearing down on him through the glass, making him sweaty and uncomfortable, but Katsuki ignores it. Soldiers through the discomfort and pain because maybe, just maybe, if he pulls away now, if he leaves the front door unguarded he might miss...

He squeezes his eyes shut.

It's pointless.

He knows it, deep down.

He's being useless. Being a Deku.

He should be strong. Unrelenting. Should be standing stall and swallowing it all down and be-

Katsuki buries his face into his arms, quietly screaming into them with enough strength that his body shook and seized. The sound is a buildup of energy from weeks of waiting, weeks of hoping, weeks of being disappointed, over and over again.

A cycle, a wheel that finally spun out of control.

Why wasn't he coming back why why didn't he have his Quirk there's no fixing it Katsuki you know it you're useless useless a failure a fucking defect-

Once the first sob escapes, he can't stop the tears.






In all honesty, Katsuki hadn't expected to run into Todoroki when leaving school. He’d taken a route out of the school specifically to avoid the hordes of excited students. Todoroki seemed have had the same thought, for when he walks around the corner of the corridor, he’s greeted by the sight of said bastard standing in front of the stairs, about to head down to the ground floor.

Upon hearing his loud, stomping footsteps, the taller boy turns around. Katsuki bristles when their gazes meet. The sight of that single blue eye makes the hair at the back of his neck rise up.

(It never failed to.)

“Out of my way, popsicle.” Katsuki grumbles, snarling.

Todoroki offers no resistance as he shoulders past him. The lack of response, while expected, only makes Katsuki’s blood boil even more. The festering rage simmers just underneath the surface of his skin, searching for a way out. It takes all of his will to not spin around and punch the damn bastard in the face.

Katsuki puts one foot on the first step-

“Why?” He hears Todoroki call softly to him. Katsuki halts, not turning. Not yet. The other boy’s tone flat as ever but for once it was tinged with a edge of confusion. Ha. So the robot had emotions, who knew. “Why are you so fixated on winning against me?”

Katsuki grinds his teeth so hard it hurts .

Why aren't you? He wants to yell at the dumb brat. At that moment, he wants to grab the taller boy, shake him violently, slap him upside the head. Make him see. Make him understand .

The helplessness burns at him, but he holds back.

For all of his brash attitude, there's a lot Katsuki holds back.

The chains are fraying though, rusting, groaning and creaking under the weight of lies and truths and expectations , of days spent standing at the doorstep of his home, waiting for someone who would never return. Waiting for a tall, looming figure to step through the doorstep, fire burning like a crown upon his head, a familiar form that had never failed to bring a rush of pride and love in four-year-old Katsuki’s heart.

You got the shiniest, most powerful Quirk in the class and you're just cruising along instead of putting your back into it, you bastard.

Because what was the point in winning when the guy you fought against was half-assing it? When everyone could see who between the two of them had the superior Quirk? After that fight with Deku, Todoroki’s battle with him might as well be a commercial cut.

Everyone could see that.

“It’s nothing personal.” There’s a moment where Katsuki hesitates, where he thinks on what he’s about to do. Then he remembers why he was even here in the first  and his resolve boils like lava, hardening into something jagged and unbending. “Then again, that would be a lie.” He snorts.

A pause. His skin tingles with something -excitement- as he tilts his head back and looks at his classmate in the eyes.

Should he?

There was no going back from here.

...he already knows the answer.

Even Mitsuki said it; Katsuki was just as much of a spiteful little bastard as his parent.

“I just wanted to see if the defect could one up the masterpiece.”

He watches with bitter amusement as Todoroki freezes .

Eyes widening, mouth slightly gaping like he'd just been slapped in the face. Face as pale as the right side of his mismatched mop of hair. The realization of Katsuki’s words slowly sinking in, leaving him off balance and mute.

It's the dumbest look Katsuki had ever seen on his half brother’s face.


“Give the old man my regards.” Katsuki cuts him off, turning away. The corner of his eyes prickle but like fuck he was going to let the other see this moment of weakness. He waves a hand over his shoulder, barely restraining the urge to flip him off. “Guess he was right after all.”

He leaves Todoroki there.

Feet rooted to the ground.

(It’s not satisfying at all.)