Foreword:

Hello!
This work wasn't my brain child. Writers and fans from RogueDruid's Writing Lair came up with this, and I took a shot.
Specifically, this work is for
A) my Nana, who gave me the title (over and over for years, though I never truly appreciated it),
B) users by the name of Vannevariable, Hazzard Overflow and several others who I can't thank enough for assisting me, because it would be wrong not to mention them,
C) ThisCat, whose story "Something Borrowed" was an eye opening experience in regards to extra-sensory imagery. I strongly recommend giving it a try. I should stress, I have not read it since starting this, nor had I read it for a while beforehand. This is not influenced by or based on SomethingBorrowed.
Like all of my works, this is an evolving story. I can't tell you everything that will happen, so please check the tags. Shipping may or may not happen. Friendships may or may not happen. I can only hope that everyone enjoys the portrayal of quirks and characters I've managed to stitch together here. Any questions, concerns or simple commentary, please leave below. I'll do my best to read through them and respond as I'm able.

Prologue: Song Scarred Soul

Patient

Midoriya Izuku

Quirk

Soul song: Can hear the manifestation of a person's health and experiences in musical form.

Izuku frowned down at his notebook.

It had been there all day, empty and staring back at him. If it were any other notebook the page would have been filled in a few minutes at most, but this notebook was mostly empty. Each page held only a few words at the top, and a single bullet point. He sighed and shut the notebook when the teacher entered the room. Whatever the teacher started off with was lost on Izuku as he glared down at the closed book.

"…but you're all going into the hero course anyways! And you have such fabulous quirks, but no using them in school!"

Izuku leaned over his desk, hands over his ears. The music played, regardless of his hearing, but he still tried every time. With everyone showing off, their songs had risen to a fever pitch out of nowhere.

"Sensei!"

Izuku groaned. Bakugo's song killed the rest with a long, low note, then rumbled to life as if to fill the space they left behind, "Don't lump me in with these extras!"

Bakugo Katsuki was all deep intimidating notes. His song played like the slow march of a breaking storm: he lorded himself over them, threatening but not dangerous yet. A bolt of lightning rang in the music when he leapt onto his desk and began his monologue. Izuku's eyes widened as he heard something ominous in his own song and he cowered in his seat as it grew louder.

"Aren't you also going to Yuuei, Midoriya?" Bakugo's music stopped.

Izuku sighed as a sad note began to peal out through the room.

The class promptly burst into laughter.

The walk home was long and dreary. It took all his mental effort to silence his song, just so that he could have a moment's peace. He didn't need the melancholy background noise to tell him that he was feeling depressed.

"If you think you'll have a better quirk in your next life… go take a swan dive off the roof!"

Izuku's quirk came with a lot of benefits. Knowing how a person was feeling and the depth of someone's emotions, having a few moments (in the case of anything significant) to react before bad things happened, lie detection... Izuku wished more than anything that he didn't know Bakugo's feelings. Hate wasn't the right word. Bakugo didn't hate people. He was determined to grind Izuku into dust through sheer force of pride, just in case people dared to compare them.

Izuku stopped in front of the bridge and glared at the pavement. A distant memory played through his mind, playing a deep melancholy sound in between the notes of his song.

"I'm sorry Izuku! I'm so sorry!"

No! I decided back then to keep my chin up keep moving forward! He stormed into the tunnel, letting his song slowly rise until it matched his determination.

Halfway down the tunnel he heard another song slithering through the tunnel, just before his own music changed into something ominous. Without that half second of warning, he'd have been caught in the arms of the slime.

"Hey, hey, you're pretty good? How'd you know I was here?" A chuckle echoed from the tunnel as Izuku backed into the sunlight, "I don't have time to talk, actually. I'll figure your quirk out for myself…!"

The slime grunted in surprise when Izuku dodged the next tentacle, and then growled when he managed to dodge the third swipe.

"Stay still!" Izuku tripped and fell, eyes widening as the music darkened. Just before the slime reached him, something new assaulted his ears.

A bell suddenly rang through the air. Izuku watched wide eyed as a manhole cover hit the street, and the owner of the new song emerged from the sewer. A drumroll echoed through the street until Izuku was sure that everyone would be able to hear this song. If Bakugo's song was all pride and intimidation, this one roared defiance and tugged at something deep inside of Izuku, as if it were pulling him into the music and grinning ear to ear all the while. A man in cargo pants and a tight white shirt crawled out of the sewer, laughing as he entered the fray.

"Fear not!"

Izuku's eyes widened. He'd never heard this song in person, but sometimes, if he talked to the right people, he had heard traces of it. It echoed, even when someone had only seen the owner. "I am here!"

The sludge villain tried to fight, but Izuku could tell there was no point. Heart songs never lied, and he was afraid of the giant man who had crawled out of the sewer. A blast of wind tore out of the tunnel, scattering the sludge and leaving Izuku in even more awe than before.

He stared as All Might zipped by, scooping up the slime in soda bottles before nodding to himself and turning to Izuku.

"Sorry for getting you caught up in that, young man! He got away from me in the sewers!" All Might laughed, and his song rose to accompany him. Izuku's eyes widened as the hero spoke, "Young man? Young man are you all right?"

"Eh?" Izuku blushed. He'd been so wrapped up in the music…! "Ahhh! So-s-sorry! I was, I couldn't, I didn't mean…!"

"No worries!" All Might laughed again, but instead of rising… the music scratched. Izuku's eyes widened again, only to turn his eyes to the sidewalk as quickly as possible. When he focused on it he could hear… something odd about All Might's song. "Is there anything I can do for you, young man? Were you harmed?"

"N-no… I, uh... heard him coming." Izuku mumbled.

All Might nodded and tucked the bottles into his pocket. Izuku shut his eyes as the wind kicked up, then flinched as All Might opened up his notebook… "Ah no!"

All Might paused with the marker just a millimeter from the page.

"S-sorry, but um, could you sign this one…?" Izuku hesitantly asked as he pulled Hero Analysis thirteen from his bag and tentatively held it out. All Might nodded, handing both back to him.

"Of course! Is there something special about that empty notebook?" Izuku stared at the autograph for a moment before he closed the book and looked at his empty Heart Song journal.

"I… my quirk lets me hear music. I've been trying to put it into words but it's hard to describe a person's song."

"I see. That's an interesting quirk. And… that other one, Hero Analysis for the Future, was it? Are you planning to be a hero?"

Izuku hesitated and turned his ear to the right. He could almost…

"Young man? Are you all right?"

"Did you get hurt?" All Might froze. His music slowed and trailed off, replaced by something Izuku could only describe as quiet dread.

"…come again?" Izuku's eyes widened. He'd done this before. Mom had always warned him about asking things like that, about people's privacy and how sometimes it was better to keep quiet.

"I… sorry, I shouldn't ask, but… your side," Izuku glanced at All Might's right side and shuddered, "I wasn't sure at first but now I can tell, it's definitely coming from your side. You're hurt, right?"

All Might's music changed slowly. Izuku was only just now hearing the dissonance between the two sounds, and it was… odd. As if the first song was fighting against the second, trying to drown it out. His first song was full of gravity and sunshine and people cheering, of victory and the wind in his hair. The second song was tired and plucky with long notes and worn instruments. The longer the first song tried to drown out the second, the more it began to fail. Izuku's eyes widened as it missed first one note, then another.

"All Might?!" All Might stared at him as if he'd stumbled upon something horrible. For a moment, the smile looked more like a marble sculpture than All MIght's signature grin. Before he could ask, the hero laughed again and spun around.

"Nonsense, my boy! I ended that fight in a single blow! Honestly, I'm not that old!" Another laugh echoed down the street. All Might crouched and bounced on his heels.

"Ah, wait, All Might, something…"

"A pro hero battles not only enemies, but also time!" Izuku was moving before he could think.

"Thanks for your support!" All Might shouted and leapt in the same motion, dragging Izuku into the air. Somewhere in the middle of their flight a trumpet pealed.

"That was too dangerous, young man. You could have been seriously injured!" All Might huffed.

Izuku and his music both wheezed as he got his breath back.

"B-b-but…"

"No buts!"

Izuku's teeth ground together as the tug of war between All Might's songs grew worse. Even his normal, bright song was groaning under the strain.

"You can't! If you leave now…!" All Might glared back over his shoulder, and suddenly his song SNAPPED. Izuku screamed at the noise, watching in terror as All Might began steaming and cursing himself under his breath. The second song quieted down as the steam grew to cover him, and then…

"ALL MIGHT?!" Izuku stared at the gaunt man left standing on the rooftop. He couldn't believe that this was All Might, but… this music was definitely coming from his side, same as it had before.

"Calm down, kid." A fountain of blood poured from the man's mouth, "I'm All Might, there's no need to scream."

"B-b-b-b-b-b…!" The man sighed as Izuku covered his mouth, if only to stop the stuttering.

"Jeez, you're something else. No point in fighting, now," All Might slumped down against the railing, "How'd you know about my side?"

Izuku had to peel his hands from his mouth, and his voice was weak when he did.

"Ah, th-the music… Your song changed… and there's something coming from your side…"

"My song changed…?" All Might stared at him in disbelief.

Izuku sighed, then took a step forward.

"Um… I c-can show you…?"

All Might watched him carefully, but when Izuku extended a hand, he took it. Izuku chewed his lip for a moment, then took a breath and pulled All Might's song out and played it aloud.

All Might's eyes widened in shock and Izuku smiled a bit.

"The, um, your side…" Izuku frowned and reached a little deeper, trying to be as delicate as possible as he pulled out the broken instrument. All Might frowned when he heard the discord in the song. After a minute or so Izuku released All Might's hand and gripped his backpack until his hands hurt.

"People, I m-mean, everyone has a song. They're all different, and it changes every single day. Y-yours… It sounds like someone who's wounded, or sick."

"…That's a very odd quirk," All Might coughed, "I can see how you'd have trouble putting it into words. I doubt I could make sense of it at all."

Izuku bit his cheek. He wanted to say something, but… he waited instead. All Might sighed when he realized what Izuku was waiting for.

"Five years ago, I was wounded in a fight with a villain," Izuku hissed as All Might pulled up his shirt to reveal the scar, "I've kept it out of the media, but I'm only able to work about three hours a day. The damage, and the surgeries, were extensive. But I'm the Symbol of Peace."

Izuku wasn't surprised to hear All Might's theme play faintly behind the rueful song his injury gave off. For a moment it seemed like All Might's eyes were glowing.

"I will not be stopped by something like this."

Izuku believed him.

"Was there anything else you needed, young man?" All Might groaned as he stood up. Izuku hesitated, but in the end, he'd pushed it down too long.

"I, um... do you think I can be a hero…?" Izuku asked as All Might stared at him blankly for a moment, "I… I've always had this dream… to be a hero, like you, fearlessly saving everyone with a smile. B-but everyone says I can't… do it."

Silence stretched out between them, All Might staring down at him and Izuku looking at All Might's feet. After a few moments, Izuku could guess what was coming. All Might's song grew so stressed that it hurt his ears. His own song died quietly, leaving him alone in the face of All Might's answer.

"…I'm sorry, young man," All Might sighed, "Heroes must put their lives on the line every day. With a quirk like yours, you could surely help people. But, a hero? That may be a bit too far. I cannot ask someone to put their lives on the line for a dream like that."

A single, mournful chime rang inside Izuku's chest.

"I do not think you can be a hero."

Izuku couldn't remember the last time he was able to walk without forcing his quirk to be silent. He wondered if All Might had killed his quirk along with his dreams, but… that wasn't quite right.

He glanced up when he heard the shout, scowling as he realized that he'd walked to the scene of a crime without paying attention. Explosions and fire rang out from the other side of the crowd. Considering the number of people between Izuku and the fight, it wasn't surprising that he couldn't hear the songs. Large groups of people were harder to sort through. Their songs floated at the edge of his mind like static, waiting for him to poke through and find whichever he wanted to listen to.

After a few minutes of dejectedly staring at the crowd, he stopped fighting. He crossed the street and stumbled along the back of the crowd till...

That…! Izuku choked when he saw the broad, inhuman grin lacing the slime. Behind the smile was a person, struggling against the grip. Without meaning too, he started picking up on the conversations in the crowd. A few minutes… I barely survived one minute, how could someone…

When he locked eyes with the victim, his body moved.

Toshinori stared at the burning alley and the slime villain within. He watched as the heroes were fended off by the boy's quirk even as the school kid tried fighting back. Even if they wanted to, no one on the scene knew how to handle a situation like that. It was a no-win scenario for most.

If only I hadn't stalled with that kid. Toshinori gripped his side as he listened to the crowd talk about 'All Might.' His hand tightened painfully around his scar when they asked where he was, whether or not the villain had gotten away.

I'm pathetic. How could I…

Toshinori's eyes widened when he heard the music. It came from nowhere and everywhere, as if someone had plugged in speakers and begun blasting the song through the alley. At first it was muted and uncertain and full of despair. Then the strings faded and gave way to a steady beat.

The crowd watched as the boy took off running into the alley, and Toshinori spewed blood at the sight. As the boy ran, the music grew louder. People screamed, the heroes lunged, and Toshinori felt time slow to a crawl. For a moment, the music slowed and the screams of the people died away and Toshinori may as well have been right beside them to hear the first boy say

"You… You looked like you needed saving…!" Toshinori felt something well up inside of him.

No.

He felt the music pulling at him. The music didn't thunder along with his heart or shake him to the core with its metal. Despite the volume, it felt quiet. Firm. A gentle push on the back. Eyes turned on the horizon, and the dream waiting there. Feet planted firmly on the ground, moving forward faster and faster until he was running.

A reminder of who he was.

A reminder of where he had started.

One for All burned when he seized the guttering flame and began to swell in spite of its sputtering. The music changed until it was something more familiar, yet alien all the same. If the first had been young and optimistic this one laughed and charged forward, pushing back fear and doubt through sheer force of will. He felt the sun on his face and the wind in his hair and even while his body burned and fought against him the music made him feel alive.

"The lesson I left you with… I should practice what I preach!" He seized the boys just before the slime could hit them and drew back his left fist, "A pro should always be ready to risk his life!"

When it was over, as the police collected the slime and people cheered and talked about the weather, All Might heard the music begin to fade. The song took the feeling with it, leaving him with the unpleasant sensation of holding his muscle form for too long. He watched as the boys were lectured and praised respectively, and his eyes lingered more on the smaller boy.

Toshinori had travelled the world over and he'd seen plenty of odd quirks. When he'd been in the hospitals there were several empathy quirks and endorphin quirks. Mind quirks were rare, music quirks were uncommon, sensory quirks were usually unique and almost always strange unless they were simple voice quirks.

He wanted to say that it was the boy's quirk that inspired him. The music had been beyond him. No words could describe it. Only feelings could come close. Music, ordinary music, did not reach into a person and shake them to their core, or fill them with so much passion.

Toshinori didn't know what to think of it.

He decided it was the boy's actions that had inspired him and turned back to the reporters.

Bakugo's song had lost its thunder. It struggled to keep up as the boy walked away. Seeing Bakugo like that made Izuku sad, even if… even if Bakugo was right, in the end.

He recognized the tune coming from the alley before he reached it and paused. All Might's music had been exhilarating before, but it was more subdued now. Izuku pinched his lip, then smiled.

It still sounded like victory.

Izuku hid his smile when All Might slid into the street and posed dramatically. With a painful screech All Might's song caved, giving way to the trudging tune of his secret form.

Not ten minutes later, he made a deal with All Might, completely unaware that he was projecting his song aloud as he walked home.

"Mom, what song are you playing?" Inko glanced over at Izuku.

His eyes were wide for a boy of four years old. Wide and curious and sparkling.

"Music? I'm not playing any music Izuku." She had looked away from the dishes and watched him tilt his head to the side.

"Where's that sound coming from then?"

"What sound?"

"The music!" Looking back at him, she smiled. He had looked as sure as only a child could.

At the time, though, she'd been…

"Izuku, playing tricks isn't nice."

"But Mom, I'm not…"

"Hush now and finish your homework."

Her quirk was practical. Nothing flashy or extraordinary, but useful. Hisashi, for all the strength of his quirk, had never been anything but ordinary. When he was four and a half without one of their quirks, Inko started paying a bit more attention.

He was six when he learned how to project. They had seen enough doctors and been through enough exams to know he had a quirk. Each doctor had a different opinion, and they were all at least a little bit right. Izuku's quirk was sensory. Izuku's quirk seemed to be mostly invisible. Izuku's quirk may affect other people in some small way, given Inko's quirk (she never let on how that last one stung).

Izuku had been so excited that day, though he wouldn't say why. He'd come home bruised and scuffed up again, but young boys were just like that, weren't they? She patched him up and smiled gently as he bounced in the chair. When she'd asked, he simply beamed the widest smile she'd ever seen (ignoring those times he tried to rival All Might) and said he'd gotten her a present.

"I wanna show you a song! It's the best song in the whole world!"

Of course his giddiness was contagious, and they were planning on going to her favorite little café for dinner, so she let him keep his secret. They dressed up and left around seven. After the meal was over, he'd gotten serious.

"Mom, can you hold my hand? I think I need to touch you." She'd been confused, but she'd reached across the table. When he took her hand, his face scrunched up.

The sound was slow and quiet. Not difficult to hear, but quiet. Strings sang like ocean waves and the wind on an early summer's breeze. A steady, somber beat padded along beneath humming woods and an occasional ring of windchimes. It sounded like candlelight on the beach the first time Hisashi had kissed her and the way she'd cried when they first held Izuku and made her feel as warm as she'd felt when she his smile earlier that evening.

"Izuku, what…" Izuku beamed.

"It's your song, mom. The best song in the whole world!"

That memory, no matter how many years passed, made her throat hurt and her chest tighten. After that, they'd talked about his quirk. She learned of all the years she'd missed with his quirk, telling him that that he was just imagining things. He told her of all his times trying to understand the songs, trying to show people or put it to words. She'd laughed when he talked about trying to learn some bigger words to fit the songs, only to learn that the kanji themselves also had songs, and those were even stranger than a person's song.

After that, she'd watched as he took off learning about his quirk. Staring at his back as he went made the ache in her chest worse every time he learned something new. Because, even if his quirk was something amazing and indescribable and beyond her, something plagued her. Something dark and nauseating permeated every new discovery and little moment that he told her about. It infected every time he wanted to show her a song, every time he asked her for help.

Deep down, she knew his quirk wouldn't make him a Hero.

Sometimes after he went to sleep, she wondered if not telling him was worse than letting him try.

She wasn't sure what had changed. He'd come home after the mud-man incident with that old spark in his eyes. It reminded her of the day he'd showed her 'her song,' and that cut deeper than any knife.

He didn't tell her about his day. Instead, they talked about the incident, and he went to bed early. She heard him slip out early the next morning, and she was waiting when he came back sweaty and exhausted. They didn't talk much after that, except when he asked for a few things. Dumbbells, some track suits, a different diet. He ate more and talked less. She watched him walk through the house like a zombie and work out even when it looked like he was ready to cry. She asked a few of her friends what she should make of it, and they weren't entirely sure what to think either.

Just let him be. Even if he can't be a hero, it's good for him, you know? It sounds like he's working hard.

Inko knew better.

Izuku always worked hard.

He confirmed her worst fears months later, when she found the application pages among his homework. She'd pulled it out of the pile without even thinking and stared as he did pushups in front of the television.

Why are you doing this Izuku?

He came to her a week before the exam, looking conflicted.

"You already know, don't you?" She chewed her lip.

"I… I saw the application…"

"Are… would you rather I don't try?"

"Izuku… not if that's what you want. I'm just worried for you."

The talk was short, and they hadn't spent much time together afterward. He was studying in his room, and she was staring at the reflection in the silent television screen. She wondered what he had been expecting. Why had he asked her that?

For all the years since that night at the café, she'd listened to him talk about his quirk. Suddenly she felt like it all hit her at once. Izuku wouldn't look at her, but she realized that he didn't have to. He could hear every word, every thought, because they were woven into her song. Ever since she'd picked the app from his homework, he knew that she was worrying.

No. He'd always known.

It took everything she had not to break, because she might have broken her son.

She woke up the next morning, tired, nursing a raspy voice, tucked into bed with no memory of getting there herself. Izuku didn't avoid her eyes, but he was quicker than usual on his way out the door. As he made his way to school, Inko sat at the table and thought. When she finally got up, she'd decided that, if he was determined to be a hero, then she would match his determination.

He needed a mother who could support his dream, no matter what.

She would be that for him, no matter what.

When they'd begun, ten months ago, Toshinori hadn't known much about Midoriya. Really, he'd known only two things for sure. First, Midoriya had a sensory quirk that manifested as… music, for lack of a better term. Second, he'd thrown his useless self into a no-win scenario on pure instinct.

Slowly, over the course of their training, Toshinori's curiosity had gotten the better of him. He was raising a successor, after all. Even if he was to die along the way… he wanted to know who Midoriya was beneath all the fidgeting and the muttering and the odd way he looked at people. Well, that's how he thought about it anyway. He started slow and asked about Midoriya's quirk. Midoriya gave him the name, and a short description.

My quirk is called, um, Soul song… I can hear the manifestation of a person's health and experiences in musical form.

Toshinori had hummed and thought nothing of it until that evening, when he couldn't stop thinking about it.

"Midoriya," He'd stopped the boy before training the next day, earning a curious look in response, "can you tell me about the mud-man incident again?"

Midoriya hadn't really seemed to understand, but Toshinori goaded him into it. Then Toshinori stopped him mid-story to make sure.

"Ah, wait, how did you dodge him?" Midoriya blinked a few times.

"My song changed and then I heard his song coming from the tunnel behind me."

"…You said you knew it was behind you because you could hear it, right?" Midoriya nodded. "So… you can hear the songs of everyone around you? Even if you don't know they're there?"

"Well, yeah," Midoriya frowned. "People's songs are always there. I hear them like footsteps."

As if that said it all.

In a way, it did.

"Midoriya, you can hear my injury from my wound, yes?" Midoriya nodded. Toshinori stared at him for a few moments before he coughed and waved the boy down to the beach.

Number three: Midoriya's quirk gave him a lead on anyone trying to sneak up on him.

After three months, Toshinori was… confused. He'd taken to writing the list of things he learned in his phone, and he grew more worried about it with each passing day.

Midoriya

One: has the soul of a hero.

Two: Seems to think his quirk is ill suited for heroics.

Midoriya's Quirk

One: Can gauge a person's well-being, emotionally and physically, after a few minutes of listening.

Two: Allows him to hear people coming similar to any physical noise.

Three: Warns him of anything important/dangerous happening a few seconds beforehand.

Four: Capable of projection, in small doses and quiet volumes.

Five: Sarcastic?

Six: Objects have songs too, sometimes.

Seven: Music can be influenced, and so influences the person to whom it belongs.

Toshinori was impressed by the what he'd learned. More often than not, though, he found himself wondering more about what Midoriya left out. For being a fanboy and obsessing over other people's quirks, the boy had all but written off his own. Just thinking back on their conversation about the mud-man made Toshinori wonder just how much the boy actually relied on his quirk in general.

When the boy collapsed, Toshinori wanted to be upset. Instead, before he could finish his lecture, he heard the music again. Instead of the optimistic, steady beat he'd heard back in the alley, Midoriya's quirk played something insistent. It halted Toshinori, and when Midoriya looked up and exclaimed that he had to work harder than anyone else, Toshinori felt the music shake him down to his bones.

He's looking that far to the future, huh…

When he revised the plan, Toshinori thought back to the slime villain incident. He thought of the songs he'd heard, and how it had affected him.

"Midoriya, would you show me the song that plays when I'm in my hero form?" Midoriya had looked surprised, but excited as he accepted. Toshinori's smile hurt when he heard the music playing. It was the same music that had driven him to save Midoriya in the alley, just after Midoriya had given his conviction in words.

Toshinori blinked and looked down at Midoriya in shock.

His quirk… played my own song for me? With that much effect? Midoriya smiled and went back to hauling the junk gladly. He doesn't inspire people because of who he is… He inspires them in spite of it. But… that's not quite right either.

Toshinori saw a few things that worried him, too. Midoriya didn't talk about having friends. He never spent any time outside of school with other kids his age or talk about anyone but his mother. Sometimes, if Toshinori guided him along, Midoriya would talk about times he went out to learn about his quirk. He enjoyed talking about those little adventures most of the time, because they led to him muttering about heroes and quirks and their songs. But they were short and littered with trouble. For the life of him Toshinori wondered how someone like Midoriya managed to find so much trouble in the first place.

Eight: Gives subtle information about quirks and intentions.

Around month seven, he noticed the music more often. He was surprised by the music and the boy both. Several times he caught the sound just before Midoriya lifted something that seemed a bit too heavy, or when he pushed past what should have been his limit. Occasionally, when Midoriya looked out over the ocean, Toshinori felt the music whispering quietly between them. Even if he couldn't understand or put the sounds to words, he found himself looking forward to hearing that music. It happened more when he spoke up and encouraged Midoriya, so he began offering more inspiration. He learned when to offer it and how.

He realized (a bit too late) that when Midoriya wasn't letting the music play, he was worried. In the ninth month, the music tended to sputter and die just after he'd accomplished something. Midoriya was guarded and quiet. For some reason, he was more apologetic than before as well. Toshinori could feel the boy's gaze on his back often, and when he turned to look Midoriya pushed himself even harder. Whatever was bothering him was pushing him even harder than before (considering his self-destructive nature that wasn't a good thing).

On the morning of the exam, he arrived at six to find Midoriya already finished. More than finished. Suddenly the sun broke over the horizon and Toshinori heard something ring out across the shore. A battle cry reverberated from Midoriya's chest, but more than that his song began screaming defiance alongside him with more body than Midoriya could ever manage himself. It blew like a fierce gale at Toshinori's back, urging him forward. Coals inside of him suddenly blazed to life, drawing One for All out before Toshinori could do so himself.

When he caught the boy and looked him over, Toshinori finally realized what he'd been trying to put his finger on for ten months.

Nine: He inspires people by being who he is, because who he is brings out the best in everyone.

Izuku stared up at the gates of Yuuei, shaking like a leaf.

I'm really here?! Songs passed by him constantly, all echoing with a sense of awe and determination. A few were laced with worry and doubt, one was definitely sick, that one over there…

"MOVE, DEKU, or I'll kill you…!" Izuku bounced out of the way as the storm rolled past him. Bakugo's music had grown even more wild than it had a year ago, if that was possible, but he had avoided picking on Izuku ever since the incident. Maybe they weren't friends, but it was a start. Izuku had always loved listening to Bakugo's song. Despite everything, it was one of his favorites.

I… I need to do my best too. Izuku swallowed and forced himself to smile. This is it… my first step…!

Before he could step forward, he paused. Somewhere, just over his shoulder judging from the sound, was a song. Normally he would have taken it in and kept moving but this…

He'd never heard anything like it.

Izuku spun around, catching the attention of a brown hair girl with pink cheeks and a scarf. Before he could remind himself that he was staring (and obviously making the girl uncomfortable), the song washed over him.

Her song was bubbles floating in a chilly spring morning. Bubbles that popped with a flash and a giggle, like children running barefoot through the snow. Chimes reminiscent of his mother's song broke through, only to be muted when she frowned at the strange boy who was staring at her… wait…

"Ah, So-s-sorry…!" Izuku bowed frantically, turning his eyes to the sidewalk. The song was quieter now, and the bubbles were full of smoke instead of light. A deep bass note thrummed beneath her tune that reminded him of Bakugo's thunder, but instead of breaking through the sky, hers clung and drifted like a thick, creeping fog of starlight.

After a moment, she laughed, mixing the smoking bubbles with the shining ones.

"That… It's fine… Please stand up… People are looking…"

Izuku blushed and kept his eyes firmly on the ground.

"I, um, good luck…" Izuku said as he turned and walked away, suddenly filled with the urge to suppress his quirk until he was through with the exam. He had One for All, anyways.

Ochako watched as the weird boy left. He'd looked really embarrassed, but the way he was staring had been… weird. Like he was looking through her, or barely looking at her at all. She shivered, feeling a bit violated and a bit… flattered? No, she decided. Not flattered. Just weird.

Katsuki was quiet throughout the lecture. With Deku sitting beside him, it was almost impossible to listen to Present Mic's explanation of the practical. As soon as the hero walked on stage, Izuku had started giving off a faint music that sounded like a puppy staring up at a person.

Shit doesn't even make sense. Katsuki growled. Deku never made any sense. Not since Katsuki had beat him up and sent the boy home with the biggest smile anyone had ever seen. People around them didn't notice the music, of course. Until they did. Then they hated Deku, same as Katsuki.

"Whoever is giving off that awesome vibe, please turn off all your music for the presentation!" Present Mic shouted.

Katsuki blinked. Suddenly Deku was blushing and ducking in his seat.

The revelation that the nerd was projecting without thinking about it was… new. Deku's music quirk was useless, sure, but why was it changing? Why could other people hear it?

Halfway through the lecture, someone stood up and yelled at Deku for being rude to the other examinees, even though the idiot had already turned his quirk off. That was pretty funny, but it wasn't enough to soothe the rage that was starting to build in Katsuki's gut. Deku glanced over at him a few times, worried (and for good goddamn reason), before he scuttled out of the theater in fright. Watching the little nerd flee was about as satisfied as Katsuki would get 'til he got to actually kill things, he decided.

Toshinori stared at the screen, watching as the students took off through the streets of the facilities. Every time Midoriya, or the blonde boy with the explosions, appeared on screen Toshinori followed them closely. Bakugo (Toshinori had to think about that one) was a star from the beginning. Any robots who got too close were decimated with accuracy and ferocity that was more like an animal than a teenager. Midoriya… Midoriya was flunking. Hard. If he was honest, Toshinori hadn't expected the practical to go well, but… he'd expected a little bit more. Midoriya was running around frantically, not doing anything productive at all.

When he heard the music start up from nowhere Toshinori finally realized what Midoriya meant all those months ago, talking about his quirk. A few moments after the music started up, someone pressed the button and released the zero pointers. Toshinori focused on ground beta, watching carefully. Quietly the music began to ramp up, changing from something desperate…

"Is someone playing music? What's going on?" Toshinori blinked in surprise as the teachers began searching themselves.

They can hear it? Something resonated in Toshinori, before he could ask, and he spun to face the screen. Apparently, several of his fellow teachers had the same idea, because they all turned to look.

Toshinori grinned. Midoriya's song had grown throughout their training. Optimism and determination had been given some spine and pushed to the limit. A frantic, rushing beat forced the teachers up onto their feet in shock as the quiet green haired boy raced toward the robot.

"What's he thinking?!"

Ochako stared as the creepy green haired boy began running towards her. She'd only paused for a second, wondering where the ominous music was coming from, when the rubble had trapped her ankle. Now she had to be saved by… her eyes widened as he ran past her and crouched-

The frenzied beat gave way to a long, bright chorus. Some of the frenzy was still there, but the only thing Ochako could hear was-

"SMAAAAAAAAASH!" Between the boy's leap and his fist striking the face of the robot, Ochako's breath caught.

The music was definitely coming from above, from that boy, and quietly, she heard something come from the rocks beside her. A quiet tune full of awe, and why not? Above her, the boy was ringed in a halo of sunbeams, facing down a massive robot and glowing… wait, glowing?

When he struck, Ochako squeaked. The impact (even on the ground, ten stories beneath him, his attack created a gale that cleared the rubble from her ankle) caved in the face of the robot with enough force to crack the pavement beneath her feet. A long moment passed, leaving him suspended there in the sky.

Ochako hoped that she wasn't the only one who'd seen.

Before she could be truly grateful, the boy began to fall. The music was back, but instead of frantic, it was insistent and afraid. Ochako bit her cheek and slapped the first spare part she could find, pushing it up into the air and leaping on as it rose.

For a week after the exam, Inko wasn't entirely sure what to do. She caught him smiling at the fish they were having for dinner and… well, she'd been a bit frantic over the whole thing. He wasn't talking to her yet, but she'd started hearing Izuku's 'music' playing throughout the house at odd times. The sound worried her.

He sounded… empty.

When he gave him the letter and he disappeared into his room, she worried just outside the door. She heard some scuffling, a frantic shout of… no, couldn't be All Might. Couldn't be.

She didn't stop worrying until she heard the sound of trumpets and pure, unbridled joy coming through the door. Quietly, she slipped out and went to buy a little celebration desert.

Afterword:

Just in case this was an odd chapter, here's a brief summary.
Izuku met All Might and stumbled upon the world's greatest secret, then was offered a part of said secret. He said yes, obviously.
Toshinori began training him, and over that time he did his best to learn about Soul Song, Izuku's natural quirk. Which isn't terribly easy, because for Izuku Soul Song is like One for All is to All Might. Remember how well Toshinori's explanations worked? Yeah. Lot of blood and sweat and tears went into that one. But we made it, and hopefull they will too.
Inko. Ah, my complex is showing, isn't it? I love her, but let's be real. She took a long time to realize what was going on, and just how bad Izuku's home life was. His quirk really is a bitch, huh?
Soul Song, for anyone wondering, gives Izuku a lot of information. He has to parse through it all, and learn each person individually, but overall it's really just a lot of information. His quirk can't affect anyone physically beyond making loud noises. One for All, though... that's a whole different box of tricks.
I hope you enjoyed reading!