When you turned five, you'd had your quirk for a few months.
The doctors didn't even scratch the surface about what it is you could do.
This third nervous system wasn't a physical one like a network of nerves.
It was like a network of atoms that flurried and spread within every single cell like its own organism.
You remembered running around your backyard after the dragonflies and beetles in the summer bleeding into fall. It made you laugh whenever your mother would yell at you to come inside, but you asked for just a few more minutes in the sun. It seemed like no matter what, you could never run out of breath even if you ran for hours.
This quirk had a mind of its own, you see.
And no matter what, its primary purpose was to protect your body from harm.
So as you ran and ran and ran it never let you run out breath.
But, as you ran after the dragonflies and the beetles, inevitably, you caught one. And when you opened your hands to let the bug free again, it didn't fly.
So, you looked down at the creature in your palms. As you did, you smile began to fade.
Because the dragonfly was dead.
***
Present Day
Hero basic training started today. All Might was teaching.
Everyone seemed super hyped about it, but to be honest, you weren't too excited.
Also, there was costumes involved.
Changing in the locker room was a new experience.
Essentially, your costume was just a black body suit made of breathing fibers. You liked the look, but even with its very protective nature and the fact that it covered you from head to toe, you couldn't help but feel a bit exposed.
After all, when you can feel the entire contents of the air around you through your clothes, they don't feel a lot like clothes. You requested agility and conforming capabilities, but breathability was the most important component.
With the suit came a black mask to cover your nose and mouth.
"Nice costume Y/n!" Momo complemented. Hers was more revealing than yours but she was really pretty in that too so you got distracted again.
"Th-thank you. I like yours too." You responded anxiously.
Of course, once you saw the boys in their costumes it was a different playing field.
Kaminari's looked pretty cool. He matched your color scheme with his black jacket and little receiver near his ear. Kirishima looked ready for battle with his headgear.
The two of them complimented you on yours the moment they saw you.
Although, you chose not to notice when Mineta and Kaminari began whispering things as they looked at you and Yaoyorozu.
Instead, you found the boy you'd been waiting to see all dressed up and put an arm around his shoulders once he walked out of the boy's changing room.
His costume was, as expected, pretty plain with the exception of his entire left side being covered in some sort of ice sheet.
"I think you took my calling you ice man too literally Shoto." You teased, his side glance of disapproval making you rub his hair playfully. "I'm kidding! You look great."
"Thank you." He replied as you jumped down. "You too."
"I know right." You put your hands on your hips and looked down at yourself.
"The mask." Shoto pointed to the black cloth-like thing around your neck. "Is it for your quirk?"
"Yeah." You said, spinning it around so it looked more like a hood. "I probably won't need it."
Todoroki nodded, but as he was about to say something again, someone lightly knocked into him and as they were walking past.
The air changed a bit as that happened.
Bakugo: dressed in heavyset gear that bared his arms and hid the upper part of his face behind a mask.
He actually looked kind of intimidating in his get up. The black mask that spiked out with his hair exaggerated the red of his eyes as they found yours.
He barely noticed Shoto as he was about to yell at him to get out of the way.
Instead, he noticed you.
He hadn't seen you out of your uniform or with your hair up like that before. And he'd be lying if he said he didn't think it was a drastic improvement to finally be able to see all of your incredibly annoying face.
Of course, he kept these things to himself.
The costume hugged you nicely, yeah, but it didn't give him any hints about your powers.
It was better to stop looking you up and down for now and focus on his real opponents like Deku.
"Watch yourself icy hot. You don't wanna set me off." He bit out at Shoto, moving past the both of you and towards the training grounds where All Might was waiting.
"You keep looking at him." Shoto noticed as you watched the angry boy stalk off. "Do you like his costume?"
"What? No." You said unconvincingly.
You had to admit though, Bakugo's arms didn't look half bad unclothed by his uniform blazer.
Hunching your own shoulders you added, "Mostly, I just want to ask him what his shoulder workout routine is."
Shoto gave a half smile because he didn't understand your humor a lot of the time but found it best to smile so you didn't feel bad.
Once you two reached Ground Beta, UA's official training grounds, All Might gave his announcements to the class.
"They say clothes make the pros and you young ladies and gentlemen are the pros! From here on you are all heroes in training! Seeing you all wrapped up, you look so cool! Now that you're ready! It's time for combat training!"
You listened to the man talk like a soldier with your hands behind your back and the respect he deserved.
As a young child you admired All Might, but given the person who raised you, that admiration didn't last long. Endeavor made it clear that your purpose was to train beside Shoto. Make each other better. Become worthy of defeating the teacher that stood in front of you now.
Shoto interrupted your thoughts by tapping your arm and pointing to the building you'd be competing in.
"Since we'll be indoors," He said, "Using your quirk should be easy--"
"I'm not using it." You interrupted. "Not unless I have to."
"I don't understand." Shoto said with concern. "During the assessment, with the softball, you were perfectly capable of utilizing your quirk. What's changed?"
"That was different. I had to prove a point. And I was using it on a softball, not a person."
Shoto opened his mouth to respond, but All Might was already making his announcements.
"We will have seven teams of three! One will have to go twice as a villain or hero group depending on points! I will choose these teams randomly from this hat!"
Why does he always sound so excited? You thought to yourself, but then again english class with Present Mic was a whole other level of too loud for you.
Your ears began to ring so you almost missed when All Might called your name.
"Young Y/n, Bakugo, and Iida! You shall be the villains!"
"Hm?" You thought you might have heard that wrong.
"You again, huh?" Bakugo was standing next to you now.
He did look intimidating. Far more than before. He even seemed taller if that was possible. When he crossed his arms, his muscles bulged out. Those grenade like things on his wrists looked so heavy it would probably take both your arms to even pick it off the ground.
Perfect. A hot head to manage while you were just trying to pass a class. How fun.
When Bakugo gave you a side glance, he noticed you were smirking just at the thought.
"Why are you smiling like that!? Are you mocking me again!? I'll punch that smirk right off your face you loser!" He yelled, putting up a fist.
You shrugged.
"You can try, but I guarantee you I'm faster with those tanks." You said, flicking the gauntlet on his raised arm. Looking him up and down, your grin widened. "If we're being frank, I'm probably faster either way."
Surprising you, Bakugo grabbed the wrist that touch his weapon and held it tight in his gloved hand.
The pressure instantly made your body tense, your quirk beginning to stir beneath your skin at the sensation of a threat.
Remembering to just breath, you tried to control the shaking violence beneath your skin that wanted to blow away the boy holding on so tightly.
But when you looked into his red eyes, Bakugo's intensity wasn't aggressive at all. Actually, he just looked focused rather than angry. His mouth was loose, jaw unclenched. It was as if, he was searching you for something, trying to look deeper.
You didn't know, but he felt the slight vibration when he grabbed you, the sudden change in your demeanor as you'd all the sudden gone quiet.
There was something up with you.
He always tried to ignore it in class, but it always came back to this thoughts like an itch at the back of his brain.
Finally, he loosened his grip.
"You're on my team." He said, calmly, matter of factly. "So I don't have time for you to piss me off." With that he let you go and stepped back into line, facing All Might. "Just stay out of my way."
Thankfully no one really noticed, because they were all paying attention to All Might.
"And now for the heroes that will go against them!" All Might announced, picking names from the box. "Todoroki! Mydoria! Uruaka!"
Bakugo smiled wide as he heard Deku's name, but you only turned to Todoroki.
"Will today be the day I even the score with you, Shoto?" You teased with a smile.
"I won't go easy on you." He retorted playfully.
"I wouldn't expect anything less." You winked, following Iida and Bakugo as he went the other way. "See you on the battleground."
***
Ground Beta was built as a training facility for combat training.
Essentially a big abandoned city replica. In this building, you were tasked with protecting a "weapon" as a fake group of villains till time ran out for the heroes.
Observing the tin can of a weapon, the boy dressed like a cyborg began, "I am concerned having to be associated with criminal behavior. However this is only an exercise."
You nodded, thinking of possible strategies to defend against your opponents.
"So, I assume we have a plan!" Iida said, hands on his hips, prepared to take on his role as a villain.
As you readied yourself to talk over some options, Mr. arrogance walked between the both of you and headed towards the doorway that led to the lower levels.
"You two stay here and guard the weapon. I'll handle the fighting." He said, banging his fists together excitedly.
"Hedgehog." You called to stop him from going further. "I know you and Midoriya have some history, but maybe you should keep it out of this."
"Yeah?" Bakugo looked at you over his shoulder. "And who do you think you are, telling me what to do?"
"It's just a suggestion. Personally, I don't care much if we win. But you seem to. You want that outcome? Let's start working together."
"Whatever. But Deku is mine."
"Good." You said, putting two earpieces in that came with the costume. You also put in your registration form that your quirk had a little side effect when it came to hearing so they included them.
Walking up to where Bakugo was waiting for the timer to start, you halted at his side and added, "It's better if we guard against the people we know anyway. I know how Shoto fights so our only struggle is going to be focusing on Uraraka. Iida, if she gets past us, do you think you can handle her?"
"Affirmative." Iida said, beginning to look around the room for ways he could guard against her.
You nodded to acknowledge him.
That's when the timer beeped and the door opened.
"C'mon. I'm not waiting for you." Bakugo grumbled.
You began walking down the hall and to where the three others would begin their goal as the heroes.
"I'm gonna roast that damn nerd today." Bakugo said. There was a big smile on his face, his eyes shinning redder than usual.
"Dude, you look like a villain."
"We are the villains, moron!"
You chuckled, glad to see his dark side easing up a bit.
Whenever he was like that it put you off. Made teasing or mocking him all but impossible too.
For the most part, right now, you were just trying to focus on this activity. The only issue was Bakugo and this vendetta he had against poor Izuku.
Even now, he looked lost in thought over the matter, his teeth grinding together.
However, as you were looking forward, trying to be in the moment rather than in the past like him, Bakugo was able to get a better look at you.
There were no prying eyes of other classmates nor was Shoto at your side. It made observing you far easier.
You actually weren't bad looking. That is when you kept your mouth shut.
"Hey." Bakugo said calmly as you began walking down the flight of stairs.
"Hm?"
"Why do you even wear those things?" He asked, pointing to the suppressors in yours ears.
"Already wanting to know my deep dark secrets, Boom boy?" You kidded, trying to steer him away from any topic involving your power.
"I thought I warned you not to call me that."
You scoffed and rolled your eyes at him, resuming your paced walking since you were sure the 'heroes' would arrive soon.
When you looked down at Bakugo, however, you noticed he wasn't actually enraged or annoyed.
Was that actually a genuine question on his part?
Though you and him had your fair share of witty exchanges in class where he would scream at you and then long drawn out silences followed... there were times you caught him looking at you with a curiosity he didn't look at others with.
And it wasn't just curiosity about how he could beat you. It was curiosity about what you really were beneath the shields of the Todoroki name as well as the facade of humor and quiet.
It was like he wanted to ask 'who are you' without actually saying the words.
"My quirk." You said, seriously now, making Bakugo's head perk up. "It's kind of sensitive." You clarified, taking the earpieces out and showing them to him in your hand. "It can cause this tinnitus-like effect where my ears ring or I start to hear frequencies at a high volume like a radio. Anyway, when it acts up, things like headphones or compresses help drown out the mess."
Bakugo didn't respond.
He didn't even give any reaction past looking down at your palms than up at your ears.
Why did you get so serious? And why did you act like it was more of a nuisance rather a weakness?
Bakugo shook his head a bit, his frown returning.
Whatever.
All this meant was you finally did have a weakness he could exploit in combat. That was all that mattered.
"What do you think of Deku's quirk then? Is it real?" He asked.
You shrugged your shoulders.
"If it isn't that was a hell of a throw the other day."
You thought back to that softball pitch that broke Midoriya's finger.
He was such a brave kid. You envied that about him- how he wasn't suited for attacking, combat, facing whatever it is this program would throw at him. But he did it anyway. That was more than you could say for yourself.
"Was he really lying to me all those years?" Bakugo grumbled, his fists clenched along with his teeth.
"I haven't known him long, but Midoriya doesn't seem the type to be dishonest." You tried to say. "Especially not to someone he admires so much."
Bakugo's body sort of short circuited as you said the word admired. No matter how much Izuku thought of him, he was still an enemy in his mind.
"Yeah?! Who asked you!?" Bakugo yelled.
"You did, actually." You rubbed your temple from his volume. "About 10 seconds ago."
Growling to himself, Bakugo picked up the pace once you reached the middle levels of the building. Here there were a bit more windows, but the terrain was still unfavorable.
Actually, for your quirk it was kind of perfect.
Urgh. Annoying.
"What is your quirk anyway?" Bakugo asked after a while, as if reading your mind. "You ever gonna be brave enough to tell me or are you gonna beat around the bush forever?"
For some reason, he was closer now as you turned around. The hallway wasn't so narrow that he had to stand this close to you. It caused your breath to hitch and your body to jump when you realized it.
As if on cue, that third nervous system of yours woke up.
Air pressure, temperature, nitrogen- 78%, oxygen- 21%-
Shut up. You thought to yourself, shutting your eyes and shaking your head.
But he was too close.
You could feel the heat radiating off his body, the intensity of his eyes, hear his slow steady heartbeat, the rushing of blood in his veins.
It was like your sensory input was in overdrive.
Proximity: 15.3 centime-
Hitting yourself in the head a few times, you groaned and muttered to yourself, "Urgh. Shut. up."
But your quirk kept sensing the conditions around you. It wanted to know them. Wanted to keep you safe.
Body temperature 37.7 degrees
Env. temperature 25 degrees
Outward body temp of 38.2 degrees
Foreign substance of carbon, hydrogen, nitrogen, and oxyge-
Wait. What?
"Fine, don't tell me." Bakugo said, beginning to stalk off. "I'll figure it out one way or another when I beat you."
"Wait. Stop." You ordered, grabbing his bare arm and tugging him back to you as you were finally able to shut your quirk up.
"Heh?"
"Your costume." You whispered to yourself.
Bakugo wasn't listening to you though. He was distracted by the fact that you were touching him. And he couldn't decide whether it felt annoying, strange, intriguing, or all of the above.
Whatever it was, he needed your hand off him.
"Is it-" You started asking, but he began to pull away. "Are you storing- Would you stop walking?!"
"Don't give me orders!"
Grabbing him again, you tugged the hand on his other arm till his glove came off and you threw it to the ground.
"Hey!"
Ignoring him entirely, you tugged on Bakugo's calloused hand which was nearly twice the size of yours till it was firmly in your hold.
Bakugo's breath was pulled from his chest.
Both of your hands held his gently, eyes fixed on it as you skid your fingers across his palm.
Nobody had ever touched his hand so reverently before. Not even his doctors who were charged with figuring out his quirk when he was a kid.
They were all too afraid to. And you were so soft for some reason.
He was usually so tense everywhere, including in his knuckles and fingers. The way you were so careful, so gentle; he never noticed how nice it felt to just relax those muscles.
In fact, this made him realize, maybe nobody had ever touched him like this at all.
"It's... Nitroglycerin?" You asked, collecting the beads of sweat on your fingertips.
Once your bright and curious eyes met his, Bakugo blinked.
He spent a second or two looking at you.
Because what the hell was this feeling?
It didn't last very long.
Breaking out of his trance, Bakugo looked down at his own hand again and tugged it away from you with a growl.
"That's how my quirk works you idiot." He said, pushing you out of the way to retrieve his glove you'd tossed to the floor. "My sweat combusts the explosions."
"No I got that already. But you're storing it?" You asked.
"How'd you know about that?"
"I can sense it. It's a higher concentration in your gauntlets." You said, pointing to them.
Bakugo smirked.
"Impressed are ya? These aren't just for show. I had to ask for them especially so that I..."
He began talking about his costume a bit long windily and though you wanted to listen, something else caught your attention.
There was a noise coming from further down the halls, around the corners so you couldn't see.
But you felt it.
A disruption in the air.
Bakugo was still talking, but you didn't hear any of his words. Instead, you knelt down to the ground a few steps in front of him.
"Are you listening to me? What the hell are you doing?"
"You want to know what my quirk is?" You asked, which shut him up very quickly. "This is the only time I'll use it during the fight so pay attention."
Closing your eyes and releasing a breathy exhale, you let your fingertips make contact with the ground.
Okay. Do your thing. You thought to yourself.
Suddenly, all the sensory information you'd been pushing away from when Bakugo set you off by getting too close, returned.
This time you welcomed it all.
You see, people tend to think purely on sight when picturing things. Then they add sound, feel, all of the other senses.
But to someone like you, it was sight that came secondary to everything else.
When picturing a place and a way to defend it, trying to see it with your eyes was by far the weakest option prone to the most mistakes.
But try to see it with feel? With sound?
You get an entirely new advantage.
Walls, floors, concrete, darkness-- nothing can block your view when you can sense everything between them.
"Around the corner to the left." You said, your eyes still closed. "Two of them. Their third member is coming from the other direction. They're walking, but the one coming the other direction is slower. I think its Shoto being cautious because his temperature is slightly more erratic than the other two, so he knows I can feel him."
Sort of confused, Bakugo raised a single brow as you opened your eyes and stood back up straight.
But he quickly forgot about that as soon as he heard the same footsteps you'd predicted.
"Then handle him." He said, his hands warming with his quirk beginning to rile awake. "I've got Deku."
"Wait, don't rush out." You tried to warn him, but he went ahead anyway. Shoto knows how to--"
But you didn't get a chance to finish as Bakugo jumped out and caused an explosion, followed by a blinding spurt of ice.