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English
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Part 1 of My Hero Venom
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Published:
2025-06-21
Updated:
2025-11-12
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57,026
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26/?
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Crawl Under Your Skin

Summary:

Izuku didn’t get a quirk from All Might. He got something else. Something alive. Hungry.

Now he’s learning to be a hero in a world built on lies, with a voice in his head and Venom under his skin.
He's learning, too late, that power has a price.

MHA x Venom/Marvel fusion. Uses elements from all canon medias.

Notes:

This has been kicking around in my WIPs folder since 2021 and I finally decided to polish it up and post it in case it's something worth continuing. I've been hyperfixating on Venom lately, and that's combined with my love of MHA.

UA is a university, so everyone's 18+. This means that Izuku was forced through 3 extra years of systemic abuse and quirkism without social support through highschool.

The student ages were adjusted, the adult ones are selectively adjusted based on plot.

This starts just after the Sports Festival. MHA follows canon prior to that. Any changes will be explained in story.

Edit: I'm trying to stay as faithful to canon as I can. I'm using elements of all versions of canon, for both MHA and Venom. My head canon is a more Tom Hardy-centric Eddie with comic elements; Venom is comic centric with Hardy tempering.

MHA is going to lean more manga, with anime elements.

Edit edit: I keep getting spammed with people trying to sell me art. Stop. Seriously. What the fuck kind of money do you think fanfiction writers make? Zero, because writers are treated like shit and can't monetize fan work. If I can't sell my stories, I'm not buying your fan art.

(See the end of the work for other works inspired by this one.)

Chapter 1

Notes:

Edited 8/15/2025

This is a series now. I've been slowly creating, editing, and adding a history/lore/exposition dump called My Hero Venom. Some pages contain spoilers, but I tried to hide the Overview and Timeline spoilers behind 'details' tags so there is a Marvel -> MHA fusion guide for people not familiar with one or the other canon, and to point out canon divergence.

(See the end of the chapter for more notes.)

Chapter Text

Izuku didn’t take the usual route home after class. He hadn’t for a week. Not since blinding agony, broken bones, and terror from a group of former Aldera classmates. They were trying to ‘help’ him show off his ‘miracle quirk’ by beating him senseless and breaking the fingers on his right hand. 

While Bakugo had gradually faded from the sea of antagonists with age and ego, others had only grown more bitter as reality of their lack of future prospects loomed - when they noticed the worthless Deku got better grades than them. Izuku was the prime scapegoat and punching bag since no one cared if a quirkless person got hurt or disappeared. But he’d made the grave sin of showing off on live television, bringing him back to the minds of those he thought he escaped. 

Being a hero student came with rules, official and otherwise. The legal standards for self-defense were stricter for them, harsher. Sometimes more-so than if they were normal vigilantes. It was meant to prevent over-eager trainees from going rogue. All it did was make him easier to hurt.

So he grit his teeth and took it.

Even with a quirk, Izuku was still powerless. Still the same easy target he’d always been. The same boy they laughed at for dreaming. His guts had twisted and raged at the reminder, even as he’d curled up and protected his head and neck with practiced, pathetic efficiency.

A week later, his fingers still lanced with phantom blows.

Every time they ached, he thought of the Sports Festival. Todoroki’s flames, the heat blistering through the air, the crowd cheering like it was a show and not two barely adults breaking apart for approval. His bones snapped again and again, and still he kept standing. Still he smiled like it didn’t hurt.

Recovery Girl’s warning echoed like a verdict: 

She wouldn’t heal self-inflicted damage anymore.

It was intended as an ultimatum to All Might for not training him right. Izuku knew that - past the sting of familiar thorns. He didn’t blame her.

It was easier not to think about it anyway. Easier to stay quiet. Easier to smile when no one was looking too hard.

He turned the corner toward the campus side gate and froze. 

Two figures.

One leaning against the rusted fence like he belonged there, hood shadowing his eyes but not the annoyed slouch. The other stood stiff, arms crossed and posture all wrong, like he didn’t know how to look casual even when he tried.

Shinso. Todoroki.

The ache behind Izuku’s ribs pulsed once, sharp and sour. His instinct was to run.

They didn’t speak at first. Just looked at him. Like they were trying to decide whether to call out or back off.

Izuku’s smile was practiced and automatic. It cracked anyway. "Didn’t think I’d run into you two here," he said, voice light and awful in his own ears.

Shinso replied, dry. "It’s the route people take when they’re avoiding attention."

Todoroki’s gaze moved slow, like it had weight. Like he was cataloguing every inch of Izuku. As was common of late, his mismatched eyes drifted towards Izuku’s arms and hands. "You didn’t answer my messages," he said, neutral and direct.

Izuku shrugged. "Must’ve missed them."

"Right," Shinso muttered, unimpressed. "Like you’ve been missing every lunch, free training block, and support check-in."

"I’ve been busy."

"With what?" Todoroki asked. Not accusing, just blunt. Honest. It was worse somehow.

Unable to meet their eyes, Izuku stared at the ground. "I’m fine."

"You don’t look fine," Shinso said, sharp. "You look like you haven’t slept in a week and you’re trying to hide it under sarcasm and a hoodie that hasn’t fit since first year middle school."

Izuku flinched. His hands balled in his pockets.

"You haven’t spoken to anyone in class. Even Uraraka and Iida," Todoroki continued. "But you’re talking to yourself again."

That one landed.

Izuku’s throat closed up. He stepped back. His fingers itched and burned. He could feel it again - the thing behind his ribs, crawling, restless, waiting for a moment to escape.

Not yet.

Not now.

Not in front of them.

"I’m just tired," he said. "I have homework. I’m fine."

"You’re not," Todoroki said again, stepping closer. "You don’t even believe that."

"What do you want from me?" Izuku snapped, voice cracking. "You want me to say it hurts? That I can’t sleep? That I-That I keep thinking maybe if I just take a swa-"

He cut off. Swallowed it back. Too late. His eyes stung without permission. He’d almost admitted more than he could ever take back.

Shinso’s eyes narrowed at the aborted words. Todoroki blinked, slow and steady. None of them moved.

Mentally backpedalling, Izuku shook his head. "It’s stupid. Forget it. You shouldn’t worry-"

"Drink," Shinso interrupted, pulling a bottle of water from his bag and holding it out.

Izuku stared at it. "That’s not going to fix anything."

"No," Shinso said. "But passing out from dehydration would make it worse." He indicated the wet tracks on Izuku’s cheeks. All of 1-A knew that Izuku was capable of a disturbing amount of tears when he got going.

Izuku took it.

Todoroki stepped beside him - shoulder to shoulder. Not blocking. Not hovering. Just there.

Izuku didn’t speak again. But he drank. And somewhere inside, the thing behind his ribs… purred.

They didn’t talk much on the way to Izuku’s place. Shinso kept pace with a lazy slouch that somehow never faltered despite still sporting lanky limbs from puberty. Todoroki walked like a ghost. Soundless, but his bearing was too regal to be ignored.

Izuku didn’t even question it when they followed him to the front door. Didn’t question the weight of their presence. It was either this or crumble. He hadn’t invited them. He hadn’t expected them to care. They’d barely spoken a dozen words to him - before the sports festival. 

Now, they walked beside him like it was the most natural thing in the world. He didn’t have the strength to push them away.

The apartment smelled like grilled fish and lemon disinfectant. Too clean. Too sharp. It used to smell like cinnamon and miso and the faint singe of burnt rice when his mom got distracted watching dramas. 

He couldn’t pinpoint when it had changed. But it hadn’t smelled like home in years.

His mom’s voice floated in from the kitchen.

"Izuku? Is that you? I made- oh!" She turned, hands still damp from the sink. Her smile was bright, practiced. "Todoroki-kun! You placed first, didn’t you? You were amazing!"

A mild frown tugged the corners of Todoroki’s lips but he gave a shallow, polite, bow. "Thank you, Midoriya-san."  

Inko beamed. Then her eyes landed on Shinso. A beat passed. Her smile dimmed.

"You’re the boy from Izuku’s first match. Shinso - the brainwashing quirk, right? I should scold you for scuffling like toddlers. Poor Izuku’s nose was all crooked!" She said it with a small laugh, like it was a joke. Like she didn’t mean anything by it.

The bored expression Shinso normally sported turned stony. "It’s fine now," he said flatly. 

"Thanks to Recovery Girl," Inko needled. "I hope you’re being a good influence for my Izuku."

Shinso didn’t respond. He darted a glance at Todoroki, then Izuku’s plainly bared arms and hands. They were more scar tissue than skin.

Noting the double standard as well, Todoroki’s jaw clenched. The temperature of the room dropped several degrees but he gave no other indication of his feelings.

Izuku’s head lowered to stare at the floor. His stomach twisted, feeling like eels were tying knots inside. His mother hadn’t looked at him once. Not really. Not since the festival. Not since he came home with injuries too deep to explain.

"Well," she continued, "dinner’s almost ready. Todoroki-kun, would you like to stay? I always make too much-"

"I’m not hungry," Izuku said, strained.

Inko blinked. "Sweetie, you need to eat-" She didn’t look at him when she spoke. She hadn’t looked at him in days. Like if she didn’t acknowledge it, it wouldn’t be real.

Somewhere in the yawning pit of hurt and depression, something darker sparked. It burned where it lodged in his chest. It built like a physical force, pressing up his throat until he couldn’t stand it. "I said I’m not hungry anymore. Shame on you for insulting a guest." The low fury coursing through him was hidden under quiet disappointment in his voice.

The atmosphere in the room suddenly felt tense, like the calm before the storm. 

The other two men braced to witness an argument or punishment. Distantly, the smell of grilled fish was starting to make Izuku sick. The ache behind his ribs pulsed once, sharp and sour. 

Lately, the sensation had started humming at odd times. Usually after battle, before sleep, when his blood was loud in his ears. Like now, at his own mother’s blatant quirkism. The consequences of backtalking didn’t even cross his mind, smoldering anger in Shinso’s defense giving him strength.

Said man opted to remove himself from Inko’s sight and stepped into the living room without asking. Todoroki followed a second later, wordless.

Inko gave them a grimace of a smile. "Boys," she said. "Make yourselves at home." She disappeared back into the kitchen. The silence she left behind scraped like a dull knife.

Izuku stood in the doorway for a few more seconds. Breathing shallow. Shoulders locked. "She means well," he mumbled.

"That’s the worst part," Shinso said. He looked resigned. Inko’s reaction seemed to be normal to him. 

The realization didn’t sit right with Izuku, but he couldn’t bring himself to address it. Not right now, though he filed it away for later. He weakly gestured to his bedroom door before leading the way, to escape Inko’s disapproving spectre. 

The room was dim, when they entered. He didn’t bother turning on the light. The glow from a street light outside spilled just enough through the blinds to paint outlines across the walls - posters faded with time, edges curling, their colors dulled. Hero merch lined one corner of the room like a tarnished shrine, dusty and untouched. All Might figurines. Model suits. A cracked acrylic standee of Sir Nighteye.

This room used to be his sanctuary. Now the walls felt like strangers watching him hold together with tape and routine. He hadn’t dusted the All Might shelf in months. Couldn’t bring himself to touch the symbols of hope that didn’t feel meant for him anymore. The only shelf that still saw use held nearly thirty notebooks of quirk theory and battle tactics that he had filled to the brim in his 18 years. 

Shinso glanced at the merchandise with a raised eyebrow, voice softly amused rather than condemning. “You still keep all this?”

Izuku sat on the bed and shrugged. “Habit… I’ve been meaning to get rid of it.” 

Todoroki stood by the window, curiously taking in the room. “You used to believe in them.”

“I still do,” Izuku said. Then added, quieter, “Sometimes.”

Silence stretched.

Shinso lowered himself into the desk chair, spinning once without looking at anyone. “You don’t have to talk to us. But you could try not lying to our faces after we,” he gestured between himself and Todoroki. “Told you our truths. That’d be a good start.” A bitter edge tainted his tone, he pulled an apologetic face at it slipping through.

Izuku didn’t respond. His fingers picked at a loose seam on his blanket.

“I’m not good at this,” Todoroki said suddenly. “But I don’t want to watch you fall apart. So… if this is where we sit in silence and pretend that makes it better, then okay. But I’ll be here again tomorrow.”

Shinso nodded. “And the next day. You’re stuck with us now.”

Izuku looked up. Slowly. Eyes shadowed but not empty. “…Why?”

“Because,” Shinso said, “we saw you. Now we can’t unsee you.”

"And you bled for us." Todoroki's gaze drifted down to Izuku's hands, “You never asked why we didn’t stop you.”

They each fell into their own brooding thoughts.

Later, after the others left, Izuku climbed onto the roof. He didn’t remember using his quirk. He just… was there. Staring down. Counting the stories between him and the pavement. Ten floors. Give or take.

The city below blurred into motion. Cars, lights, people scurrying like ants. It felt paradoxically safe from up here. Distant. Like nothing down there could reach him.

UA’s roof had been his hiding place since day one. Quiet. High enough that he could breathe. But that was before.

It had been days since he could draw a full breath.

The roof of the main building was locked now. Maintenance, they said. No one mentioned the blood on the railings. Nightmares and stress after the USJ had driven him to coping habits he’d thought he’d grown out of. He’d gotten careless one day and bled more than normal. A noise from the stairwell had spooked him into leaving before he could clean up the evidence.

The wind slapped his face, cold and sharp. It didn’t hurt as much as it should.

He remembered All Might’s face. The disappointment. The doubt. "I’m sorry, young man. You can’t be a hero without a quirk."

He remembered his mom sobbing, begging him not to go to UA. Saying he should do something safer. Saying heroes got killed. Saying he should stop making her worry.

They were all wrong. Or maybe he was. He didn’t know anymore.

He exhaled, shaky. The breath stuttered on the way out.

No one noticed until he shattered. No one looked until he bled.

He wasn’t planning anything.

Not really.

He just wanted to see what it would feel like to lean…

His foot shifted forward. Just an inch.

Then something pulled.

Not hard. Not panicked. Just a nudge, barely there. Pressure at his ankle. Cold. Damp. Firm.

He froze.

The wind kept blowing, but the world went still.

His heartbeat stuttered. “What-?”

The pressure moved, curling around his leg like a lazy snake. Holding him steady. Preventing weight from shifting any further.

He stumbled back instinctively, away from the edge. Away from… From what? Nothing was there. He’d expected a concerned hero but only air greeted him.

His chest heaved. Fingers clenched at the fabric over his ribs like he could tear it open and make sense of what he felt. Something had touched him. Was still touching him.

Something inside.

Another breath. Not his. Calm. Controlled. Watching.

Then, finally, words. Not out loud. Not quite. Just there, in his skull. “ That was close. "

Izuku’s legs gave out and he dropped to a crouch. “What the hell,” he whispered. “No. No, no, no-”

We didn’t mean to scare you. ” The voice came again, thick, low, and steady. Familiar in the way pain sometimes is, though Izuku had never heard it before in his life. “ We didn’t want you to fall.

He pressed his hands to his head. His fingers were shaking. His breath hitched. That wasn’t a stray thought. That voice wasn’t his.

“You’re not real,” he muttered. “This is stress. This is - this is a breakdown. You’re a hallucination. You’re-”

And somewhere, beneath skin and scar and bone, something coiled tighter. Not demanding. Just… present. Holding on.

“What-” His back hit the rooftop. Cold concrete scraped his palms as he scrambled away from the edge. “Who-who’s there?” No answer at first. Just that same presence. Warm, steady, coiling behind his ribs like a second heartbeat.

" We noticed every time. When they didn’t. When they wouldn’t. We wanted to speak. But you were so hurt. So loud. " The voice complained.

“Stop. Stop it.” His voice cracked. He pressed both hands to his ears, like that would shut it out. “You’re not real. You’re just another hallucination.”

" I’m not. I promise. "

“Then show me.”

A pause. Heavy. Considering. " You can't handle us yet. "

Something slid against his wrist, cool, damp, steady. Not painful. Not threatening. Just there. It was the same as what held his leg to keep him on the ledge. Izuku flinched like it burned anyway. His breath hitched again, shallower this time, caught between instinct and reluctant fascination.

" We don’t know who we are anymore, " the voice said. " But you called us power. We want to be more than that again. "

He stared at his arm. Nothing visible. No marks. Just a lingering pressure, like being held underwater with no splash to explain it.

His ribs ached - no, something inside him shifted. Slow and deliberate, like it was stretching for the first time in years.

The part of him that wanted to scream stayed locked behind clenched teeth. The part that wanted to understand kept breathing. “Is this a quirk?” he rasped.

No reply. Just a soft hum in the back of his skull. Not words, but intent. Protective. Watching.

The wind cut sharper now. The rooftop felt colder than before.

He didn’t get up. Didn’t speak again. Didn’t trust it.

He wasn’t sure if he was alone anymore. And that was worse.

Notes:

Curious what I've been up to? Tumblr in my profile.

The title is inspired by an amazing Venom fan song and video I found: Your Better Half by JT Music https://youtu.be/QG14ndjvmPU?si=lvPVerdXn10aDd8-