MHA: Transmigrating into Mina's Brother as Majin Buu

Author's Note: So, may be updating this story regularly for now as... well I wan't to do more fics, but I have so many now that I just feel guilty leaving them behind, so I've decided to clear my backlog! gonna speed up this one as I said earlier and well end it sooner as I pretty much just do copy paste cannon and add the scenes it takes me much less time to think through what to write.

I'm going through canon but it may take too long honestly so I'm going to do time skips between events, mainly the most fun ones up to the paranormal war. If anyone has any recommendations please drop them, I'll probably do depending on the suggestions from 5 to 10 events maximum (depends if you guys can convince me to do more) adding in between those little daily life chapters, maybe every 2 or 4 chapters depending on the type.

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All Might's first punch connected with the Nomu's torso, and instead of the creature flying across the plaza like it should have, it simply absorbed the impact and countered with a devastating uppercut that actually made the Symbol of Peace stagger.

"What?" All Might's surprise was audible even from where Anim stood.

"Surprise!" Shigaraki giggled, scratching at his neck with four fingers while keeping his pinky carefully raised. "Nomu was made specifically to fight you! It's got shock absorption to counter your strength! This boss fight is gonna be epic!"

Anim watched the exchange with growing dread. All Might was strong—stronger than anyone had a right to be—but the Nomu was matching him blow for blow. And there was something else, something about the way All Might moved that seemed... off.

"Kill All Might," Shigaraki said to the Nomu, his voice dropping from childish excitement to something colder. "That's your main quest. Complete it."

The creature lunged at All Might with renewed fury, its massive fists swinging in combinations that would have liquefied a normal person. All Might dodged and weaved, but Anim could see he was being pushed back.

"This is wrong," he muttered, his protective energy starting to pulse again. "Something's really wrong here."

"What do you mean?" Jiro asked, though she was watching the fight with obvious concern.

"All Might should be wiping the floor with this thing. The way he talks, the way everyone talks about him... he's supposed to be invincible."

But the Symbol of Peace was clearly struggling. Each exchange left him breathing a little harder, moving a little slower. The Nomu, meanwhile, showed no signs of fatigue.

That's when Anim noticed something that made his blood boil. While All Might was focused entirely on the bio-engineered monster, Shigaraki was moving. Not to help his creature, but toward where Aizawa lay unconscious.

"The player's distracted," Shigaraki said to himself, his four-fingered grip flexing as he approached their teacher. "Perfect time for a stealth kill. This'll give me extra experience points!"

"Like hell," Anim snarled.

He moved without thinking, his body stretching as he launched himself across the plaza. Shigaraki was so focused on Aizawa that he didn't see the attack coming until it was too late.

Anim's fist, surrounded by his protective energy, caught Shigaraki in the side and sent him tumbling across the concrete. The hand-covered villain rolled to his feet with surprising agility, his red eyes now fixed on Anim with murderous intent.

"Rude!" Shigaraki complained, brushing dust off his black outfit. "I was in the middle of a combo attack! You're supposed to wait your turn!"

"Yeah, well, I never was good at following rules," Anim replied, settling into a fighting stance between Shigaraki and their unconscious teacher.

"Fine! If you want to be an impatient player, I'll deal with you first!" Shigaraki lunged forward, his hand reaching for Anim's face with all five fingers spread wide.

Anim twisted away from the grab, his enhanced reflexes keeping him just out of reach. Whatever Shigaraki's Quirk was, he clearly needed to touch his targets to activate it.

"Hold still!" Shigaraki whined, swiping at him again. "This is supposed to be easy! You're just a tutorial boss!"

"Tutorial this," Anim said, his stretched arm wrapping around Shigaraki's wrist and yanking him off balance.

The villain stumbled, and Anim was there with an uppercut that should have ended the fight. But Shigaraki managed to get his hand up at the last second, all five fingers spread to catch Anim's fist.

The moment of contact should have been disastrous. Whatever decay Quirk Shigaraki possessed was clearly meant to be lethal. But instead of Anim's hand crumbling to dust, there was just a brief flare of conflicting energies as his protective ki met Shigaraki's destruction.

"What?" Shigaraki stared at his hand in confusion. "That's not supposed to happen! My Quirk always works!"

"Maybe your game's glitched," Anim said, following up with a left hook that caught Shigaraki across the jaw.

The villain went down hard, blood trickling from his mouth as he stared up at Anim with a mixture of rage and genuine confusion.

"This isn't how the script is supposed to go," he muttered, touching his bleeding lip with four fingers. "NPCs aren't supposed to be this strong. And my decay should have worked!"

"Sorry to disappoint you," Anim said, advancing on the fallen villain. "But real life doesn't follow video game rules."

"Kurogiri!" Shigaraki suddenly screamed, his voice cracking with panic. "Emergency extraction! The game's broken! The NPCs are cheating!"

A swirling portal of dark mist opened behind Shigaraki just as Anim lunged for him. The villain rolled backward through the portal, his red eyes locked on Anim with a hatred that was no longer childish.

"This isn't over!" Shigaraki snarled as the portal began to close. "I'll figure out your cheat codes! And next time, I'll have better gear!"

"Kurogiri!" came another voice from near the fight between All Might and the Nomu. "Get Nomu too! We're done here!"

The mist villain materialized near the bio-engineered creature, even as All Might prepared to deliver what looked like a finishing blow.

"DETROIT..." All Might began, his fist pulling back with gathering force.

Kurogiri reached out to envelop the Nomu in his portal, but All Might was faster.

"SMASH!"

The devastating punch connected just as the portal began to form, sending the Nomu flying like a cannonball through the air. The creature crashed through the facility's reinforced walls and disappeared into the distance, leaving a Nomu-shaped hole in the USJ's structure.

"No!" Shigaraki screamed from his own portal. "My final boss! You broke my final boss!"

"Shigaraki, we need to leave NOW!" Kurogiri's voice was strained as he maintained the portals. "The heroes will have reinforcements soon!"

"This isn't fair!" Shigaraki complained, but he was already backing through his portal. "The difficulty spike was too high! I wasn't ready for the secret final form!"

In seconds, both villains had vanished through Kurogiri's portals, leaving behind only destruction, unconscious thugs, and the echoing sound of All Might's triumphant blow.

"Is everyone alright?" All Might called out, though Anim noticed he was breathing harder than he should have been after such a short fight.

"Sensei's hurt bad," Anim said, kneeling beside Aizawa's unconscious form. "He needs medical attention."

"The other students?"

"Most are scattered through the facility," Jiro reported, her earphone jacks still plugged into the ground to monitor sound throughout the complex. "I can hear them fighting in different zones, but it sounds like the villain retreat is causing confusion."

"Wheyyy," Kaminari added helpfully from where he was sitting, his brain still fried from overusing his Quirk.

All Might nodded, then looked directly at Anim with an expression that was part pride, part concern.

"Young Ashido," he said quietly. "What you did just now—protecting your teacher, standing against that villain—was very heroic. But what happened when he tried to use his Quirk on you?"

Anim looked down at his hand, where he could still feel the residual energy from blocking Shigaraki's decay. "I'm not sure. My protective energy seemed to interfere with whatever he was trying to do."

"Protective energy?"

"It's... hard to explain. Like ki, maybe? Something I've been developing recently."

All Might's eyes sharpened at the mention of ki, though he didn't say anything immediately. Instead, he just nodded and turned his attention to coordinating the rescue of the scattered students.

But as heroes and police began arriving to secure the facility, Anim couldn't shake the feeling that his confrontation with Shigaraki had raised more questions than it had answered.

The villain had been so confident in his Quirk, so sure that touching Anim would end the fight instantly. The fact that it hadn't worked seemed to have genuinely shocked him.

And if Anim's protective energy could interfere with Quirks...

"What exactly am I becoming?" he wondered, watching as paramedics worked on Aizawa.

Majin Buu, he had honestly forgotten with all the recent school life but his powers and appearance we're a genuine copy from him.

Yet as he remembered that, he began planning his future growth, specially for those Nomu's... 

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Author's Note: Yeah, sorry to disappoint ya folks who just want a complete story, I was just meaning to lay the groundwork and then do various time skips for this one, sorry if it gave the wrong impression, did give forshadowing that it will be kinda fast before, though.

Anyway, Good night my fellas!