Hero to Villain (And Villain to Hero)

(Inspired by Batman, Injustice, Marvel, The Boys, the Transformers 2023 comic, and Irredeemable)

This is a story of role reversals, corruption, and redemption.

And it all begins at the start of the new school year for U.A., with Izuku Midoriya entering into the school with One for All in his gut and reinvigorated dreams of heroism and greatness in his heart...

Except he is not alone. He's got his twin sister, Izumi, by his side, the one person who has supported him and his dreams all his life.

But all of that changes when the USJ comes to pass. The villains attack, and Izumi is confronted by one particular villain. A woman by the name Shizuki Shigaraki.

Shizuki is one of the children that have been raised in the orphanages run by All for One, and has been brought together, alongside Tomura and several others, to form the Children of All for One, a subsection of the League of Villains that have been conditioned to be totally obedient to All for One and his desires, the perfect minions and pawns. Shizuki, much like the rest of them, has been pumped full of quirks by All for One, and has been trained and programmed to be a deadly assassin and fighter. Worse yet, she, much like the rest of the Children of All for One, has been conditioned to love combat, to relish violence and to take sadistic pleasure in the act of murder...

And this is her first day, and Izumi is to be her first kill.

Shizuki, in this instance, is acting much like the average MHA villain, or even just the average Shonen villain. She's braggy, she's bloodthirsty, and she's eager to claim her first kill...

And then... she does.

Shizuki murders Izumi.

Shizuki murders Izuku's sister.

Upon seeing this, Izuku is thrown into a rage and begin to wail on Shizuki, throwing her against the ground and laying punch after punch into her, threatening to kill her in turn for murdering his sister before his classmates are able to pull him off.

Izuku is angry, furious, vengeful...

And Shizuki?

She is horrified.

She now has the blood of an innocent person, someone her age, on her hands. But it's not as happy and joyful and exhilarating as All for One had promised. It is terrifying and sickening and has Shizuki feeling like a monster.

Shizuki is pulled away by a fellow Child of All for One, and they beat a retreat. When they get back to the bar that the League of Villain were using as a hideout, All for One asks Shizuki how it feels to kill for the first time, but Shizuki's only reaction is to throw up and tearfully ask All for One why it didn't make her happy, why it made her feel like a monster. All for One tells Shizuki that it will get easier over time, but all Shizuki can do is curled up into a ball and rock in place, traumatised by the blood on her hands and seen as a weakling by the rest of the Children of All for One.

And Izuku, meanwhile, stews in guilt, anguish, and anger at his sister's funeral, desperate to avenge her.

From here, we see two stories begin to play out in parallel to each other. We see Izuku's side of the story, where he is forced to come to grips with the loss of his sibling and the growing anger that he is feeling, though he still very much remains on the heroes' side, and we also see Shizuki's side of the story, where she is still part of the League of Villains and the Children of All for One, but is slowly coming to terms with her murder of Izumi as well, and is forced to confront the morality of her actions.

But then, soon enough, the Kamino Incident begins, and Bakugo is being held prisoner by the League of Villains. At this point, Shizuki has been forced to accept the fact that she has murdered someone, and has to deal with that fact for the rest of her life.

And she decides that she needs to make All for One pay for what he has done, and what he convinced her to do.

And she begins by freeing Bakugo, attacking and taking down the League of Villains, and convincing the rest of the Children of All for One to join her.

As such, the Children of All for One turn against their unwanted father and attack him alongside All Might, defeating the villain and fleeing before the rest of the heroes can arrest them.

Meanwhile, Izuku is told this by Bakugo, but adamantly refuses to believe it, his anger continuing to get the worst of him, and he convinces the rest of his class to think the same as well. In an ironic twist of fate, Bakugo would end up becoming Izuku's minder as he begins to slowly slip into darkness over the death of his sister.

Elsewhere, Shizuki and the Children of All for One, now separated from the League of Villains and off on their own, are left purposeless and confused on what to do with themselves now. However, the group end up coming across Eri and Overhaul, and would end up saving the little girl from her abusive father and bringing down the Shie Hassaikai all on their own. Worse yet, they discover that Overhaul's Yakuza were actually supplying the HPSC with the quirk-erasing bullets made from Eri's tissue, and uncover a web of corruption within hero society.

As such, the Children of All for One, now led by Shizuki, decide to right the wrongs of their past and become vigilantes, rebranding themselves as the New Dawn and beginning their battle against the corruption of hero society.

At this point, it should be made clear that Shizuki is primarily inspired by Cassandra Cain, the second Batgirl, from DC.

Meanwhile, Izuku is confronted by Sir Nighteye, who demands that he hand One for All over to Mirio. At this point, Izuku is becoming lost in his anger and desire for revenge, and lashes out at Nighteye for it. Worse yet, his devotion and idealism of hero society slowly begins to morph into angry fanaticism in reaction to the New Dawn's various activities in exposing the corruption lying within hero society and taking down corrupt heroes and politicians. This is only made worse when the public begin to express support for them, much like they had done with Stain, and Izuku, using his position as the supposed heart of Class 1-A, convinces the rest of his class to hate them as much as he does for what happened to Izumi.

Elsewhere, the New Dawn happen upon the MLA, the canon fight ensues, and the New Dawn find themselves at the seat of the Meta Liberation Army's power. However, Shizuki, having grown and evolved much since the beginning of the story, has no desire to take power for herself like All for One, and resolves to use what she has been given to help the helpless and finally expose all that is wrong with the world...

By finally exposing the corruption of the HPSC, and what they had allowed Overhaul to do to Eri in order to get the quirk-erasing bullets.

This proves to be a step too far for the HPSC, and they order the heroes to attack the New Dawn and their allies. Soon, the war from canon would begin, only now the moralities have shifted and been flipped.

Now, when Izuku confronts Shizuki, he is not selfless to his core and willing to give his all to help others. Instead, he has become a selfish, vile monster desperate for revenge.

Meanwhile, his opponent, Shizuki, has come a long way since the beginning of the series, and has evolved herself from the selfish, vile monster desperate for her father's approval like she once was, and has now become one of the most selfless characters in the entire story.

This is a story of role reversals, corruption, and redemption.

This is a story of heroes who turn to villains, and villains who turn to heroes.