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The Things You Weren't Supposed To See

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Katsuki was on his bed when a knock sounded at his door. He padded across the carpet and opened the dorm room door to a dirty mop of green hair and a wide, shining smile. “Hi, Kacchan!” 


“Deku,” Katsuki grunted, taking stock of his visitor’s bare feet, his muddy pants and dirt-streaked face. His brown fingers held a blue composition notebook at his side, looking just as ruddy as he was. “The hell happened to you?”


“Training with All Might,” he said, casual and concise. “I start my internship next week, so I wanted to see if I could get up a percentage or two of-” He quieted, glancing down the hall, before leaning in with his hand cupped around his mouth. “One for All.”  


“Hm.” Katsuki didn’t say more. In all honesty, he didn’t want to talk about internships at all, seeing as the class left him behind to take supplementary lessons with Half-and-Half for his damn provisional license. As Izuku chattered on about training, Katsuki leaned on his door frame and crossed his arms. He observed how the mud flecking his cheeks made it appear like Izuku had earned an additional layer of freckles. Even after cleaning up, though, he’d definitely have a few fresh ones.


When they were little, Izuku would come out of the sun each day with more. And Katsuki, being the little shit he was, would jab each one with his index finger, counting Izuku’s exclamations of ‘Ow!” and attempts to make him stop. Katsuki wondered what would happen if he did that now, if he brushed away the dirt and counted the new freckles blanketing the bridge of his nose. 


Would he flinch away? Would he smile wider? Would he-




Katsuki flinched, pulling away from his thoughts, and tried to determine what he’d missed while stuck in his own head. Izuku had one brow raised at him, looking as if Katsuki’s attitude was peculiar. And, yeah, it was, but Katsuki wasn’t looking for someone to call him out on it. “You have what I asked for or not, Deku?” He grunted, shifting the conversation.


“Oh! Yeah, here! I hope it helps with your classes! Gang Orca can be tough to fight in a battle, but I’ve listed his strengths and weaknesses in here. I don’t know what other heroes you fight in the remedial courses, but if you need any of my other notebooks, just let me know!” Izuku reached out his hand and offered the notebook to Katsuki, who looked at the frayed corners, loose binding, and blackened cover and scoffed.


“You take this with you to train, Deku?” He asked, taking the notebook and dangling it in the air by a corner. He looked from it to Izuku and tilted his head curiously when he saw Izuku fidget with his thumbs.




“Then how the hell did it get so fucking dirty?”


“Well, uh-” Izuku smiled softly, awkwardly, at him. “Kacchan, you’re the one that burned it.”


Katsuki frowned. “When the hell would I-” And then memories flashed at the front of his mind of Izuku hunched in the corner, a thin, blue notebook in between his palms, the sound of the pages flapping when he tossed it out the middle school’s second-floor window. Katsuki ground his teeth hard and felt the ache in his jaw.


He tried not to think of the guilt buried in his gut, or the ‘I’m sorry’ that itched the back of his throat. He was sorry, and he was ready to admit that Izuku was maybe, kinda, sorta important to him. Katsuki just didn’t want to say it out loud, or let Izuku know just how much Katsuki pined for their old friendship.


And maybe something more.


“Thanks,” he said, deep and soft, too thoughtful at the moment to put his typical bite into his words. Izuku didn’t seem to think much of it.


“No problem! And, well-” Izuku swayed back and forth on his feet. “If you have questions, or you need someone to help you go through it all, I could- well, I could come over after dinner and go through it with you?”


Katsuki wondered if he was imagining the way Izuku’s ears turned red, or the way he wouldn’t look at him when Izuku’s bright green eyes had always been on Katsuki. Izuku was his rival now—his friend, though it was fledgling and fragile—and Katsuki couldn’t argue that deep in his heart, he wanted to spend more time with him. 


“Yeah,” Katsuki said, noticing the way Izuku’s hair now shielded his eyes from view. He reached forward and tucked a green lock behind Izuku’s ear, watching him blush at the contact. “It’s a date.”


Izuku jerked his gaze forward, eyes wide and cheeks red. “O-okay! Let me- Let me go and, um- I’ll go clean up!” 


And then Izuku ran down the hall and into the stairwell. The fourth floor corridor was silent and Katsuki returned to his bed to read through his notes from the remedial class and cross-check them with Izuku’s hero analysis book. 


He didn’t know when studying turned into flipping through the notebook with gross fascination at the detail in the notes, the colored drawing of their favorite heroes from their childhood, the bulky All Might Autograph at the back of the notebook, and then-





I’m sorry for leaving you. I just-



Katsuki’s gaze shifted to the corner of his bed, away from the wrinkled paper. It was wrong to look, to read a letter from Izuku to his mom. It was wrong, and he didn’t want to do it, but what did Izuku mean by ‘leaving’ her? The only time the twerp had ever been away from his mom was when he moved into the dorms, and Katsuki specifically remembered seeing a Hero Analysis No.15 book in Izuku’s hand right before middle school graduation. 


This one was marked No. 13.


That meant that whatever Izuku meant by ‘leaving’, it had happened way before they’d moved into high school. Katsuki looked down at the page once more and kicked himself for what he was about to do. He read:




I’m sorry for leaving you. I just didn’t know how to tell you how I felt without making you cry, even though I’m crying now and I know you’ll cry when you read this. But I promise it will get better with me gone. 

I’ve stopped kidding myself now, mom. I met someone today who finally convinced me I’ll never be a hero. And it hurts, and I can’t stop crying, but all I’ve ever wanted to do was help people, and I guess this is the only way I can. With me gone, you don’t have to worry. I’ve seen the way you look when I come home with cuts and bruises, and I’ve seen you cry to dad over the phone because you just don’t know what to do to keep your Quirkless son safe. But you don’t have to worry if I’m dead. You can go abroad with dad, you can be happy, and I can stop the pain that I’m in every single day because I know I’ll never be more than something people think is worthless. I can stop living with the fact that my best friend doesn’t want me anymore, and Kacchan can be the amazing hero I know he will be.

I can’t be the burden anymore, for you or anyone else. There’s something wrong with me. Being Quirkless isn’t something people will ever want or accept in this world, so I’m okay with dying. If I die, I can finally be happy, and the people I love will be free to live without me weighing them down. 

I love you mom, so never think I don’t. Even when I’m gone, I want you to know I did it for you, for dad, for Kacchan, and the heroes who don’t need to waste their time saving someone who isn’t important.





Katsuki blinked and a hot tear came to rest on the ‘o’ in ‘Love’, muddling the ink. When he saw it, he quickly swiped his hand against his eyes and cleared anything on his face that betrayed the fact that he could feel this heart splintering. It ached, it stung like the pinching of a nerve or a needle pressing deep into his skin.


It was a suicide note, wrinkled spots and smudged ink from dried-tears making the letter look worn, over-thought. The paper shook in his hands as he breathed heavily through his nostrils and glanced up at the door. Just twenty minutes ago, Izuku had been there with the brightest smile on his face, blushing because Katsuki had called their study session a ‘date’. Just minutes ago, Izuku had been happy, and just a year ago he’d planned on killing himself.


Katsuki’s hands trembled as he watched the words go fuzzy, as he tried to focus on the writing and found the words that hurt the worst. ‘My best friend doesn’t want me anymore’, and it wasn’t true because Katsuki wants him now.


He wanted him as a rival, as a friend, and as someone more important than all of that—something that made Katsuki’s heart pound, his face grow hot, and his mind say, ‘ Not yet. I can’t think of him like that just yet.’


But he could think of Izuku as someone worth living, someone valuable as a hero, even if Katsuki wanted to be a better one. And there’s no way that Izuku had meant him to see something so raw, so deep and personal, but he had, and even if Katsuki wouldn’t admit that he lov- that he liked Izuku more than he let on, he wanted him to know he wasn’t a waste. 


No matter how old the letter was, Izuku needed to know.


Because it was one thing for Izuku to think Katsuki didn’t want him around, but it was another for him to actively pursue disappearing.


Katsuki wouldn’t risk it.


His feet moved before his mind did. Barefoot, his feet slamming against the carpet, he bolted from his room and down the hall, to the stairwell because the elevator was too damn slow. He jumped the bottom four stairs when he got to the first floor, and ignored the questions of his classmates as he hopped couches in the communal area and disappeared around the corner, heading into the men’s showers. 


And then Katsuki saw him.


Izuku was at his locker, clad only in his stupid, all might underwear. His wet curls stuck to his forehead, his neck. Beads of water rolled down his tanned, bare shoulders, catching on the raised scar tissue on his arms and his muscular abdominals. 


“Yo, Bakubro! What’s up?” Denki pulled back a shower curtain, stepping out and wrapping a soft, white robe around him. At the sound of Katsuki’s name, Izuku perked up, turning towards the entrance to find Katsuki’s eyes heavy on his sweet face and curious expression.


“Get out.”


Izuku furrowed his brows. “Kacchan?”


“Not you,” he said, flicking his gaze to Denki. “Out,” he gritted. “Now!’ He slammed his fist against the wall, felt his knuckle burn with what he knew was the splitting of his skin. Blood trickled down his fingers and, noticing it, Denki bolted for the door, not wanting to get involved.


A moment later, it was only Izuku and Katsuki in that room, staring each other down, the former lookings apprehensive and the latter trying his damndest not to scream, not to grab Izuku and shake him for ever thinking something so stupid.


“Kacchan, what’s wrong?” Izuku asked, taking three strides forward so that if he reached out his hands, he’d be able to brush his hand against Katsuki’s cheek and send shivers down his spine. But he didn’t, and so Katsuki did.


He rushed forward, wrapping one arm around Izuku’s back and planting his other on the crown of his head, driving Izuku’s face into his shoulder. Izuku stiffened in his hands, and Katsuki gritted his teeth. He could feel his palms shaking against Izuku’s bare skin, feel the tremor quaking through Izuku’s body. 


“You weren’t fucking useless,” Katsuki said.


The tremors stopped, and Katsuki, worried Izuku would try to run if he didn’t let up, loosened his grip so that Izuku could step back and look into tired, red eyes. “Kacchan,” he muttered, shaking his head. “What are you talking about? I- I already forgave you for-”


“-Never think about killing yourself again, Deku.”


Izuku froze, the blush draining from his face. Katsuki could see the moment the panic set in, because Izuku grabbed his hair in his hands and pulled, releasing an incredulous laugh because, “Oh my god, you saw it.”


Katsuki stepped forward. “Yeah, Deku, I saw the note, and-”


“You- you weren’t supposed to see that. I meant to take it out,” Izuku whispered. Tears welled in his eyes, and the fear set in. Izuku stepped back, further and further from Katsuki until his back hit the cement wall and he slid down to sit in a puddle of water. He buried his head in his hands, and Katsuki, whose only instinct was to keep the tears off Izuku’s face, stepped forward. 


His footfalls echoed in the silent room as he walked to Izuku’s side, as he kneeled down beside him, and laid his hands over Izuku’s. He pulled them from his face, but Izuku refused his gaze, and that left Katsuki with the only option to release Izuku’s wrist and press his palm to his cheek, dragging him towards his firm gaze. “Deku, I do want you, okay? I was a shitty friend, but I’m here now to make up for being a dick, and I’m telling you that no matter how irritating you can be, I’d rather deal with that than a world without you.”


Izuku’s lip quivered. He whispered, “Kacchan…”


“I can’t be the best hero without you keeping me on my toes. I- I need-” What was making him say this? He’d thrown away all the barriers he’d built up slowly in an instant, forgetting about his inferiority complex, his regrets over All Might, the secrets Izuku had kept from him, and the uncontrollable urge to force down the longing he felt when he looked at him. All he wanted was for Izuku to know he’s valued.


A weak smile twitched at the corner of Katsuki’s pink lips as he looked into teary green eyes and brushed his thumb against fat freckles. “Don’t think about leaving again, okay? I need my rival, Deku.”


Izuku choked on his sob, lunging forward to wrap arms around Katsuki and bury his head in his chest. “You- you promise?” He sputtered, holding firm.


Katsuki buried his nose in Izuku’s drying curls, breathed in his earthy scent and pressed his lips against his scalp. He’d never dared being this intimate with someone, but with Izuku trembling in his arms and the knowledge that if Izuku had really done it, had killed himself and left Katsuki behind, there wouldn’t be anything to hold. Katsuki felt so goddamn grateful to hear the steady sobs, feel his warm skin on his fingertips and cradle him in his lap. ‘So, “Yeah, Deku. I goddamn promise,” he whispered against his ear, because now that he’s known what it’s like to have Izuku at his side, he won’t live a life without it.


He won’t live a life without Izuku.


Without his Deku.