A Hero in a Demon School!!!!

Izuku stood in a dark void, surrounded by a quiet and oppressive atmosphere. Suddenly, the sound of running footsteps broke the stillness. He turned, his heart lifting as he saw a teenage Eri sprinting toward him. Spreading his arms wide, he prepared to catch her in a hug—only for her to pass straight through him, completely ignoring his existence.

Stunned, Izuku turned again. This time, he saw an adult Ochako, clad in her hero costume, standing nearby.

"Hey, Eri, where are you off to?" Ochako called out.

"Oh! Hi, big sis Ochako," Eri replied with a radiant smile. She held up a small green Deku plushie and asked, "Do you know what this is? I found it in my old stash."

Izuku's eyes widened in shock at her words. 'Did she really forget about me?' he thought, disbelief crashing over him.

Ochako stepped closer, taking the plushie from Eri's hand to examine it. "Hmm... nope, I have no idea who this is," she said casually. "But it kinda reminds me of those oversized All Might hoodies I used to have years ago."

"The ones you donated to charity?" Eri asked.

"Yeah. I never even knew where they came from, so I figured someone else might appreciate them more than I ever could," Ochako explained with a shrug.

Izuku watched their conversation in stunned silence. He wanted to call out to them, to make them see he was right there, but the black mist swirling around him held him captive. He couldn't move, couldn't speak—it was as though the void itself was smothering him.

"Then I'll do the same," Eri said brightly. With that, she and Ochako turned and began walking away.

Panic surged through Izuku. He tried to scream, to reach out, but his voice was swallowed by the mist. The space around him began to shrink, the walls of the void collapsing inward until everything folded in on him, leaving him in darkness.

******

Izuku shot up from his bed, gasping for air as his heart pounded in his chest. His body was drenched in sweat, his breathing ragged.

'Izuku, can you hear me?' Nana's voice echoed in his mind. 'Come on, kid, we've done this drill before. Take deep breaths and calm your nerves.'

He nodded to himself, sliding off the bed and curling up on the floor. Wrapping his arms around his knees, he rubbed his face with trembling hands and began taking slow, deliberate breaths.

Ever since Izuku had been reborn in this new world, these nightmares had plagued him every few weeks. At first, they were about the grief his death had caused in his old world, leaving him consumed by guilt for days afterward. But over the years, the dreams had shifted. Now, they always showed the people closest to him slowly forgetting him entirely, which was even more heartbreaking for him.

The door suddenly burst open, and Sullivan strode in with his usual cheery energy. "Good morning, my precious grand—" He froze mid-sentence, his smile vanishing as he took in Izuku's disheveled state. "What happened? Are you all right?"

Izuku glanced up, forcing a weak smile. "Oh... yeah. Don't worry, Grandpa. It was just a nightmare," he said, his voice strained.

"If you say so..." Sullivan replied, still clearly unconvinced.

Izuku sat back on his bed and ran a hand through his damp hair. "So, did you need something?"

"I love the sound of that!" Sullivan beamed, his usual exuberance returning. "Oh, right! Remember we talked about roots yesterday?" Sullivan asked and Izuku nodded his head. "Well, guess what? Your brilliant grandpa has already found a solution! Opera, bring that thing in!"

Opera, who was standing right outside the door, entered the room carrying a strange black object with multiple branching extensions. It resembled a grotesque cross between roots and some kind of centipede.

"Izuku-sama, please remove your shirt," Opera instructed, but then hesitated, noticing the sweat-soaked fabric. "On second thought, perhaps you should bathe first."

Izuku nodded, "Yeah... probably a good idea," Izuku agreed, glancing at his drenched clothes. Then after twenty minutes or so, he returned and sat before Opera, his shirtless back exposed.

"This may feel a little strange at first, but please bear with it until I'm done," Opera said and Izuku nodded, bracing himself. Opera pressed one end of the strange object to the back of Izuku's neck, slowly tracing it down along his spine until the other end settled just above his hips. Then, one by one, the branching extensions adhered themselves to different points across his back.

At first, it felt strange—an odd pressure against his skin. But then, irritation set in, quickly escalating into sharp pain, as though countless needles were stabbing into his back. Izuku clenched his fists, gritting his teeth, but before long, the pain subsided entirely. The discomfort vanished, leaving him unable to feel anything on his back.

"Opera... what is this thing?" Izuku asked in a cautious voice.

"It's a type of living fabric that bonds with living organisms," Opera explained. "Rest assured, it's perfectly safe. Many stage actors use them during live performances as well as the real fights during the play."

Izuku blinked. "Wait, actual fights during plays?" He wanted to ask more but decided against it for now. Instead, he sighed and offered a small smile. "Thank you, Opera."

Opera gave a slight bow in response, stepping back to observe the results. Sullivan, meanwhile, clapped his hands in excitement. "See? Your grandpa always delivers! Now, let's see how amazing you look in action!"

Izuku couldn't help but laugh softly at Sullivan's enthusiasm, the lingering traces of his nightmare momentarily forgotten.

******

After getting ready for school, Izuku walked down the stairs and took his seat at the dining table for breakfast.

"Izuku-kun, are you comfortable with that thing on your back?" Sullivan asked, watching him closely.

"At first, it felt a little weird, but now I don't even notice it's there," Izuku replied with a small smile.

"That's good to hear. By the way, take a look at this," Sullivan said, grinning as he placed a set of wrapped gifts on the table. "I splurged a bit to celebrate your first day of school."

"Grandpa..." Izuku looked uneasy, his hands fidgeting slightly. "I really appreciate the gifts, but you don't need to keep spending so much money on me. You've already given me so much... now it feels like I'm taking advantage of your kindness."

"Nonsense," Sullivan said, waving his hand dismissively. "You're my one and only grandson! Of course, I'm going to spoil you. But..." He softened his tone. "If it really makes you uncomfortable, I'll tone it down a bit."

Sullivan reached into his pocket and pulled out a handkerchief with Izuku's name embroidered on it. "Here. Opera and I made this for you. Do you like it?"

Izuku took the handkerchief and smiled. "Yeah, it's lovely," he said, then noticed the bandages on Sullivan's fingers. "Wait—what happened to your hands?"

Sullivan chuckled sheepishly. "I'm not used to embroidery. It was... more challenging than I expected."

"Grandpa, don't hurt yourself over things like this," Izuku said with a tired sigh.

'Well, at least he's trying to be a good grandparent,' Nana remarked in his mind. 'Unlike me.'

'Come on, Nana,' Izuku replied. 'We've talked about this before. No more self-deprecating thoughts, remember?'

'Yeah, yeah... you're one to talk,' Nana retorted playfully.

Breakfast continued, and before long, it was time for Izuku to head out.

"Okay, Grandpa, I'm off!" Izuku said, activating Float and lifting into the sky.

"Be careful!" Opera called after him.

Sullivan watched him ascend, a twinkle of pride in his eyes. "So he can fly too, huh?" He pulled out a camera and unfurled his wings. "Now, it's time to follow him to school!"

Before he could take off, Opera grabbed him by the collar and dragged him back inside.

******

After some time, Izuku landed in front of the school gates, drawing the attention of many students.

'Is it because of my bag?' he wondered, glancing down. On his first day, he'd noticed that he was the only one with an over-the-shoulder bag, while all the other students carried handbags.

As he walked a few steps into the schoolyard, he overheard two students talking about him and quickly realized the real reason for their stares. They had noticed him flying without using wings. To them, it seemed like he had extraordinary mana control and a vast magic reserve, which was extremely impressive for a first-year student.

'Sorry to disappoint you, but I'm kinda cheating by using a foreign power,' Izuku thought wryly.

'Izuku, look around you,' Nana chimed in. 'You're surrounded by demons. They're born physically gifted, have magic, and can fly with wings. All One for All is doing is giving you the tools to stand on equal ground. That's not cheating.'

'So... just like last time,' Izuku thought with a sigh.

Then, from the corner of his eye, he saw someone he wished he could avoid for some time—that demon was Asmodeus Alice, the boy he managed to piss off on the very first day of school.

Instinctively, Izuku turned, planning to take another route. But a thought stopped him in his tracks. "No. I need to clear this up now before it comes back to bite me. Besides, I don't want another Kacchan tormenting me for the rest of my years here."

Taking a deep breath, Izuku summoned his courage and walked up to him. "Hey, Asmodeus. Can we talk?"

******

"Hey, Asmodeus, can we talk?" the green-haired boy asked, staring straight into his eyes and for a moment, Asmodeus Alice didn't know how to respond.

(AN:-Izuku in this AU is as tall as Asmodeus which is 5.7 feet.)

Up until yesterday, Asmodeus had been a peerless demon in every aspect of his life. His noble lineage and mastery of magic ensured that no one aside from his family ever dared approach him. Whether it was due to awe or his intimidating personality, he preferred the distance, finding peace in the fact that he upheld his family's prestige by standing out among the common rabble.

But yesterday had changed everything.

At first, Asmodeus had been furious with the green-haired boy for taking his spot. 'How could some plain-looking nobody dare to usurp my place?' he'd thought. He'd been ready to incinerate him as soon as he walked off the stage, but the realization that this boy was Sullivan-sama's grandson stopped him. Attacking him could jeopardize his mother's work, and he couldn't risk that.

So, instead of outright confrontation, he'd done the next best thing—a noble demon's approach—and challenged him to a battle. (He conveniently ignored the fact that he'd dragged the boy into the courtyard for the challenge.)

The boy, however, declined the challenge, apologized, and tried to defuse the situation. Looking back, Asmodeus grudgingly admitted that letting it go would have been the smarter move—picking a fight on the first day didn't exactly bode well for his reputation.

But at the time, his anger only intensified. He attacked, hurling spell after spell, only to see his opponent deflect everything with a casual flick of his finger. The sheer power radiating from that single movement—it wasn't even magic, just raw energy—should have made Asmodeus reconsider. But his pride refused to back down. He kept attacking, and by the time he was panting and exhausted, the green-haired boy stood unharmed, praising his magic and offering pointers.

That had been infuriating enough, but what followed was even worse. In a blind rage, Asmodeus charged with a fire blade, tripped on a rock, and almost injured a bystander. Instead of mocking him, the boy was genuinely angry—not at the insults or accusations Asmodeus had hurled, but because he'd nearly hurt someone else.

'How could he care about that?' Asmodeus had wondered, and that's why Alice had placed him into the mental box labeled 'demons I don't understand and probably never will,' alongside his mother.

And now, here was that same boy standing in front of him, asking for his time.

"Yes, what is it?" Asmodeus asked, finally regaining his composure.

"Listen, I just want to clear up some misunderstandings," Izuku said. "First of all, like I told you yesterday, I genuinely didn't know Grandpa was going to put me on the spot like that. I didn't even have a speech prepared, so I panicked and had to use that forbidden spell—which, by the way, is a total scam given how risky it is."

Izuku paused, looking apologetic. "Second, I'm really sorry for taking your spot. If I'd known how important it was to you, I would've turned it down." With that, he bowed his head, surprising Asmodeus yet again.

Eventually, Asmodeus sighed, letting out the tension in his shoulders. "Fine. I'll take your word for it—but only because I consider you my competition now."

"Thank you," Izuku said, visibly relieved. "I was worried you'd hold a grudge." He then extended a hand toward Asmodeus. "Let's reintroduce ourselves. I'm Izuku Midoriya. Want to be my friend?"

"Huh?" Asmodeus raised an eyebrow. "What is... a friend?"

******

"You don't know what a friend is?" Izuku asked, blinking in disbelief.

"I don't think I've ever heard the term," Asmodeus replied, tilting his head.

'Izuku, I don't think the concept of friendship exists in this world,' Nana chimed in. 'Try explaining it like you're talking to a five-year-old.'

"Okay," Izuku said, nodding. "A friend is someone you spend time with without worrying about things like status or power. You study together, train together, share thoughts and feelings, even hang out outside of school."

"That... sounds like an overly sentimental version of an ally," Asmodeus said, frowning slightly. "But I'm intrigued by your explanation." Then he extended his hand. "Very well, Izuku Midoriya. From this day forth, I, Asmodeus Alice, accept your offer of friendship. You may refer to me as Alice—but only because I see you as my equal. And know this: I fully intend to surpass you one day."

'Well... that was dramatic,' Izuku and Nana thought simultaneously.

But despite his somewhat funny declaration, Izuku still showed him a challenging smile, "Very well Alice I accept your challenge," Izuku said, "so then, where are we going next?"

******

"Familiar summoning?" Izuku asked as they walked.

"Yes," Alice explained. "It's a traditional event here at Babyls and one of the three events that determine our rank."

"Do you know, what those other two events are by any chance?" Izuku asked.

"It should be a flying race and mock battles against the upperclassmen," Alice said. "Our overall performance in these will decide our ranks."

"Oh, okay," Izuku said, 'I need to restart doing combat training again. Something is telling me that I'm going to need that if I'm going to stay here.'

'Yeah, sounds like a good plan,' Nana added. 'You must be quite rusty since you haven't had any real battle for so long.'

'Yeah,' Izuku thought. 'I'll need to brush up on Shoot Style and refine my Blackwhip maneuvers.'

'Then we'll start working on that soon,' Nana said firmly.

And thus Izuku and Alice arrived at the hall for the familiar summoning ceremony.

******

The first thing Izuku noticed upon entering the hall was that, once again, everyone was staring at him.

'What now?' Izuku groaned internally.

"They're probably wondering why we're walking together instead of at each other's throats," Alice explained. Izuku's face flushed as he realized he'd accidentally voiced his thoughts aloud. "Which, to be fair, would've been true—if not for you. You're quite the unusual demon, Izuku."

"Wait! So if I hadn't talked to you, you were planning to attack me?" Izuku asked, genuinely curious.

"No, but I wouldn't have been so civil," Alice replied matter-of-factly. "And I would've made sure to target you during all the school events."

"In that case, I'm really glad we talked," Izuku said with a nervous chuckle.

As they chatted, a voice interrupted them. "Um, excuse me..."

Izuku turned to see a demon girl with frizzy blonde hair and black horns approaching hesitantly.

'I think I know her from somewhere,' Izuku thought.

'She's the girl you saved from Alice's attack yesterday,' Nana reminded him.

'Oh yeah, that's right,' Izuku realized. He offered her a warm smile. "Hey! Glad to see you're okay."

"What? You remember me?" she asked, her cheeks turning pink.

"Of course! We just met yesterday, right?" Izuku lied effortlessly.

'Liar,' Nana huffed. Izuku winced as he felt a phantom smack on the back of his head.

"Oh, I'm sorry! I forgot to introduce myself," Izuku said quickly, extending a hand. "I'm Izuku Midoriya."

"Eiko... Eiko Oni," she replied, stumbling over her words as she shook his hand.

"Someone you know?" Alice interjected, looking between them.

"Kind of," Izuku replied. "Actually, you know her too."

Alice raised an eyebrow. "I do? Sorry, but I don't recall meeting her."

"Remember how you almost sliced someone yesterday?" Izuku asked pointedly. "Yeah, that was her."

Alice's eyes widened slightly in realization. He stepped forward, bowing his head slightly. "Please forgive me for putting your life in danger."

"No, please! It's fine!" Eiko said hurriedly, clearly flustered by all the attention.

Thankfully, the tension was broken when the hall doors slammed open, and their gloomy teacher from the entrance ceremony strode in.

"Silence," the man said, his voice cold and commanding. The room instantly quieted under his intimidating aura. "My name is Naberius Kalego," he began, glaring at the gathered students. "I will be your advisor. I oversee this ritual because I am dignified at all times. Today, I will determine whether you are useful trash or useless trash."

'Great,' Izuku groaned internally. 'No matter what world I'm in, there's always that teacher.'

As if reading his thoughts, Kalego's sharp gaze landed on him. The demon walked over, stopping inches away to stare directly into his soul, and said, "Especially those who rely on their grandfather's position and recklessly chant forbidden spells in public," he said coldly. Then he glared at Alice next, "And those who pick fights with fellow students," he said, but his eye twitched upon noticing that Izuku looked indifferent to his intimidation and Alice just outright ignored him. Then, stepping back to address the entire class, Kalego continued, "Incompetent students will be forced to withdraw immediately."

'Really! Is fate playing some kind of sick joke with me,' Izuku thought as he remembered the words of a certain hobo that haunted him for days, (The one with the lowest score will be judged hopeless and will be expelled from the school.)

Upon hearing that the students erupted into protests, but Kalego's withering glare and overwhelming aura silenced them just as quickly.

Then out of nowhere, he produced a small pink digital board decorated with cutesy images of animals and flowers, and... yeah it was totally killing Kalego's vibe.

The board's chirpy voice began explaining the summoning ritual steps:

A guide to basically summon a Familiars!

1. Draw a circle on the parchment with your blood.

2. Walk into the magic circle.

3. Throw the parchment into the flames.

4. A Familiar will emerge from the smoke.

Kalego's expression darkened as murmurs spread through the room. Without hesitation, he slapped the board out of the air. "Stupid guide," he muttered disdainfully.

"He hit it..." one student whispered.

"Does he hate cute things?" another murmured.

Ignoring them, Kalego held up a parchment. "Use this paper with my seal on it. If you forge one, I'll know immediately. Now, line up. You will be called one by one."

Is this going to be dangerous?" Eiko asked as she slowly raised her hand."What a foolish question," Kalego said. "You will be summoning a subordinate and making it serve you. That's what familiars are, and should a familiar disobey its master," Kalego picked up the cute board and created a hole in it. "There will be punishment. That's how deep the blood pact is. Now line up in an orderly fashion and perform a ritual when your name is called."

And so the event started and one by one, the students performed the ritual, summoning an array of strange and fantastical creatures. Izuku, meanwhile, was watching with wide eyes, his inner fanboy bubbling up uncontrollably.

'This is amazing!' Izuku thought, barely holding back his excitement. 'It's like getting your own Pokémon!'

'Stop freaking out, kid,' Nana chided. 'Did Yoichi bite you or something?'

'I mean, how could I not?' Izuku protested. 'I always wanted to have my own Pokémon when I was a child, and now I can get my own.'

'Sorry to disappoint you, kid, but aren't you forgetting something?' Nan said. 'To do that ritual you need magic, and even if you consider One For All a miracle, it still cannot perform magic.'

Izuku's enthusiasm immediately plummeted. 'Oh...'

Eiko, noticing his expression, asked, "Are you okay?" Before Izuku could answer, her name was called. She stepped forward, performed the ritual, and summoned a sleek, blue fox-like creature. When she returned, Izuku congratulated her with genuine enthusiasm.

Then it was Alice's turn. Gracefully stepping into the circle, he performed the ritual. The smoke coiled and thickened before a magnificent snake emerged—its body a creamy white with purple accents, massive horns jutting from its head, and fire blazing at the tip of its tail.

******

Gorgon Snake: A serpentine monster with macaroon-cream scales and purple highlights. It has clawed wings, massive horns, red slitted eyes, and fangs that gleam like polished steel. Its tail blazes with a fiery inferno, and it can breathe fire with precision and ferocity.

******

'Oh my god, it's so cool!' Izuku thought. 'It's like a fusion of Charizard and Seviper!'

Finally, Kalego's voice broke through his thoughts. "Izuku Midoriya, you're the last one. Get in there already!"

"Good luck, Izuku!" Eiko cheered with a thumbs up.

Izuku nodded at Eiko and stepped into the summoning circle, doing his best to ignore the heavy stares filled with curiosity and expectation. Standing in the center, he held the parchment tightly in one hand and bit the tip of his finger with a sharp intake of breath, letting the crimson bead well up. He carefully marked the parchment with his blood, drawing the required symbol.

******

Summoning.

A ritual in which demons summon magical creatures to serve as familiars.

But also...

A ritual in which humans summon demons.

 ******

As Izuku worked, a thought flickered in his mind.

'I know I don't have magic, but... what if I did? What kind of familiar would I wish for?' He paused for a moment, then smiled to himself. 'That's obvious—Mega Rayquaza.'

With that wish fueling his imagination, he held the parchment over the fire, fully expecting nothing to happen.

Instead, a blinding pillar of light erupted from the circle, shooting upward and illuminating the entire hall.

******

When a summoning ritual is performed with blood containing power from another world, it transforms into a wishing ritual... resulting in extraordinary phenomena...

******

Eventually, as the light from the pillar died down, it revealed a massive, serpentine figure emerged, coiled gracefully in the center of the circle. Its sleek black body shimmered with gold markings, tendrils glowing faintly around its majestic golden horns. The creature's piercing yellow eyes locked onto Izuku, who was staring at it with wide, sparkling eyes.

"I pulled a shiny," he muttered in awe, utterly enchanted.

'Hey, Izuku... why can I see you standing in front of me?' Nana's voice echoed in his mind.

'Not now, Nana, I'm busy admiring my—' He froze mid-thought. 'Wait... What do you mean, 'see me'?'

******

One more thing. 

The ritual cannot create a soul from nothing. Instead, it chooses between the demon tied to the summoning parchment or... an extra soul carried by the summoner.

 ******

'Nana, can you roar for me? Just once,' Izuku asked.

'What? Why—?' Nana asked.

'Just do it,' Izuku said, and a moment later, the Rayquaza in front of him let out a thunderous roar, the sound reverberating through the hall and causing many students to flinch in fear.

'Okay, Nana, don't freak out, but I think I accidentally summoned you as my familiar,' Izuku explained.

'Oh,' Nana replied calmly.

'Wait, that's it?' Izuku's thoughts raced. 'I thought you'd be furious about being turned into a servant!'

'Well, first of all, Izuku. This is not the first weird thing that has happened to us in the last few days,' Nana explained, 'and second, I'm kind of liking this form. I mean, I could literally feel the power in my body. I also think that this form will be more useful since we're going to live here.'

As Izuku tried to process this, Kalego's sharp voice cut through his thoughts. "Midoriya, what is that thing? It doesn't match anything in our records."

"It's a Rayquaza," Izuku blurted out without thinking.

"And how, pray tell, do you know that?" Kalego's eyes narrowed.

'Crap. Me and my big mouth,' Izuku cursed internally. "Uh... It told me."

"You can speak with it?" Kalego pressed.

"Not directly," Izuku said, scratching his head, "but I can kind of understand it."

The bell rang before Kalego could ask more questions. "Fine. You're dismissed."

"Thank you!" Izuku said hurriedly before unsummoning Nana and bolting out of the hall.

******

After leaving the hall, Izuku, Alice, and Eiko parted ways. Alice claimed to have urgent business, while Eiko went to meet a friend. Izuku meanwhile headed toward the distribution room to pick up his books.

'Let's see, the Basics of being a demon, curses, pharmaceutics, and the art of torture,' Izuku looked at the list of subjects in his hands and sighed, 'sounds fun.'

Then just as he reached the distribution room, the door burst open, and a green-haired girl tumbled out, rolling across the floor before crashing into a stack of boxes in the hallway.

Startled, Izuku rushed over. "Hey! Are you okay?"

The girl popped up from the pile with an unrestrained giggle. "Strike!" she declared proudly before leaping at Izuku.

"I'm Clara! My right foot's name is Connor, and my left foot's name is Murf! I was here to pick up my stuff but got distracted! Wanna pile things up and go ka-bam? Do you want candy?" She rattled off, barely pausing for breath, and again started pilling up the boxes. "Watch! I'll do it again!"

'What is up with this girl?' Izuku thought, baffled.

******

Minutes later, Izuku found himself standing in front of Clara, now attempting to 'swim' on the ground.

'So... how did we get here?' Izuku asked wearily.

'Because the teacher recognized you and dumped the responsibility of this chaotic child on you,' Nana replied, barely containing her laughter.

'I wasn't really asking,' Izuku grumbled.

"So Izuku, what should we play?" Clara asked and pointed at the pile of dangerous-looking things, "I have a lot of things! A spiky ball! A nom-nom picture book! A broken, blood-stained, family murder house set! And lots of other things."

'Oh my Izuku,' Nana said, not even trying to control her laughter anymore. 'This girl might be really the death of you.'

In response, Izuku just sighed and asked the universe, 'How the hell did I get here!?'

To be continued...