Wind whipped at Beros' hair. The helicopter was out of control. She was surrounded. The loud-mouthed spiky-haired blond hero ordered her to surrender.
Beros had her orders. Flect Turn was the only one who could save humanity from the monster All for One. She could not afford to let the heroes interrogate her. (And she could not afford to let her father find her.) "Humarise will save the world!" Beros screamed, then jumped out of the helicopter.
Minutes before she crashed into the ground, she saw a green-haired boy with wide, pain-filled eyes. He reached his hand out in her direction. Green sparks danced down his fingers.
…One for All?
Beros floated in a hazy mess of pain. She'd heard that her life would flash before her eyes when she died. It felt more like a bad drug trip sending her careening between different points in time.
She remembered being small, running to greet her father when he came home from work. He'd been so tall and massive. Back then, she'd felt safe picked up in his muscular arms. It had always been just the two of them alone in their giant mansion. He'd showered her with gifts in between his frequent work trips. He'd taught her how to use her longbow quirk.
She'd found the Nomu tanks by accident. In the basement, she'd stood still for nearly an hour, too shocked to move. Her father had mistaken her numbness for lack of moral qualms. He'd eagerly told her all about the family business, each word increasing her horror. Apparently he'd always wanted a relative to join him as a villain, since his brother wouldn't. He'd also told her about Yoichi and One for All.
That night, Beros had fled her home looking for the latest hero who held One for All. Surely they would save the world from her father.
Instead she'd been picked up by a Humarise missionary and taken back to one of their shelters. She'd been only a small, terrified little girl. They told her they'd never heard of One for All. The line of heroes must have died out a long time ago. There was no hope left. In any case, how could a vile, sinful thing like a quirk save the world? But Humarise had a plan to stop All for One and stop all the damage done by evil quirks.
Their anti-quirk rhetoric had struck a cord with her. It all made sense—her father had been driven mad by his quirk. Otherwise he couldn't committed such terrible crimes. Quirks were evil, and for humanity's sake must be eliminated. All for One, the monster with a million quirks, was long past redemption. But at least she could end him.
Humarise had been delighted by her willingness to serve the cause. They'd taken her away and placed her in an isolated cell. She was only allowed to leave for combat training. Her masked trainers alternated between berating her for her sinful quirk and praising her when she followed orders. She got very little food and water. To be fed, she had to recite Humarise's mantra every day. They said it was to free her mind from outside influences. It worked. After years of such treatment, Beros barely remembered her past. She had no will except to obey Flect Turn and Humarise.
She'd realized later that Humarise had picked her up knowing her parentage. And that they'd threatened to kill her to stop her father from moving against them. But by then the betrayal didn't matter. She would have died for the cause without hesitation, as she'd been trained.
She remembered a boy with crackling green energy. One for All still existed! Then there was hope of stopping All for One! Humarise didn't need to kill everyone, not if One for All survived, she had to tell them—
Beros felt pain. It was nearly a pleasant change of pace from the endless nothingness. Then a sledgehammer migraine hit her forehead with full force, and she wanted the dream back. She groaned and twitched.
"Shhhh, don't try to move. Daddy is here." A big, warm hand pressed against her forehead. The massive shadow looming over her had red eyes.
In her dazed and pain-filled state, Beros felt the relief of a child seeing her parent come to help. "D…?" She tried to speak.
"I'm here." All for One cradled her tenderly, stroking her hair. "I'll do whatever it takes to save you. I gave you a regeneration quirk before you ran away. It let you survive the fall. Even so, your current condition…the quirk is no longer enough to heal you. You shouldn't have thrown yourself out of the helicopter, all on the orders of those idiots. That was very foolish, dear one."
Beros shuddered as her mind started to come back. She was not safe. She was in the hands of All for One, the greatest abomination to ever exist. What if he forced another vile quirk on her? He would damn her soul even further! Desperate to get his touch off her, she thrashed. But her damaged body would barely move. A low groan came from her mouth.
"Shhh. I'm sorry, I shouldn't scold you right now." The Abomination pressed his lips to her forehead. "Just focus on getting better."
Off to the side, Dr. Garaki murmured, "I'm ready to begin, master."
Kissing the top of her head, the Abomination promised, "I'll keep you safe and well, dear one. No matter what I have to do." Those words lingered in the air ominously as he stepped away.
She had no time to feel relieved that he'd stopped touching her. The doctor fell on her, injecting something hot and painful into her veins. A metal saw bit into her arms. She wailed until a hand or a gag clamped over her mouth.
Izuku stumbled down the street, his body still smarting from his battle with Lady Nagant. He'd just rejected All Might's bento. It hurt his heart to remember the look on his mentor's face. But he had to continue alone, so as not to put anyone in danger.
A sound made his head jerk up. A Nomu leapt out from behind the building, claws extended—
Only to fall to the ground, an arrow through the head.
The archer stepped out of the shadows. She looked rather like a Nomu herself: one of her arms was made of greying zombie flesh. Both her legs were metal. A metal mask covered the right side of her face. The steel plates seemed to be welded into her skin. She had no hair. A strange contraption glowed on her chest, sending out pulses of light visible through her tattered catsuit. It appeared to be a glowing red cube located where she ought to have a heart. The horrific condition of her body made Izuku flinch. It would be unlike him to say that anyone was better off dead than alive, but in this case…he wondered. Perhaps she did not even qualify as alive.
But even despite how much she'd changed, Izuku recognized her by her quirk. He always remembered quirks. He swallowed. "Beros?"
She dropped to her knees before him and bowed her head. "It is an honor to meet you, the savior chosen by One for All." The metal voice box embedded in her throat made her words crackle like static. "I have been twisted and tainted by the Abomination beyond repair, but I managed to escape his dark laboratory. Please allow me to serve you however is necessary in order to kill him. That is all that I am good for, now."
"The Abomination? Do you mean All for One?" Izuku stepped closer, worried about her physical condition. She'd clearly been horrifically injured, but he saw no fresh injures, no way for him to help. "Um…I think you should go to a hospital. I've already decided to face All for One alone. Please turn yourself into the police after you get medical care."
Beros remained kneeling with her head bowed. "Humarise is gone. I have no purpose left except to serve you and to kill the Abomination. If you do not find me useful, then I will end my sinful existence with my own two hands." She pulled out a small dagger and held it to her throat.
"No!" Izuku shot forward, knocking the weapon from her hands.
"Then you still find use in me?" She looked up at him with tears flowing from one eye. The other eye was bionic. "Please, savior."
Gazing into those pain-filled eyes, Izuku felt her need call to him. He'd left behind everyone else because they were better off far away from him. But Beros would not be better off. Her words had been sincere—she had nothing else left. Furthermore, he did not doubt her resolve to commit suicide. If he left her alone, he would not be able to stop her.
Izuku gulped down a lump in his throat and extended his hand. "I'll let you come with me. Please don't hurt anyone, including yourself."
"I would not presume to touch you with my sinful hands, savior." With a creaking sound coming from her joints, she rose. "Thank you for your mercy. I will obey you without question and serve you with every last bit of life in my fading body."
The gleaming fanaticism in Beros' eyes made Izuku uncomfortable. But it was better than her trying to stab her own throat. Perhaps with time he could convince her to live for herself. As he resumed walking, she followed him.
OMAKE TIME!
Omake: Yoichi is Face-Palming from the Void
Beros: I must flee to a powerful person who is not as evil as my father.
Flect Turn: We're not as evil as All for One! Actually, we're way worse. He wants to rule the world, we want to outright kill everyone. Here, have a brochure.
#
Omake: The Fear No Evil Reference
Beros: Is Botan still my mother? It would stand to reason if All for One has a type—women with green hair.
Botan: I have way better taste than to sleep with All for One. I might have joined a cult but I still wouldn't stoop that low.
Inko: Hey!
#Beros was a test-tube baby #She could be Botan's daughter if Botan donated some eggs for money #Pick your own headcanon
#
Omake: Someone Finally Topped Yoichi
All for One: The bad news is that my daughter went missing. The good news is that after my brother created a lineage of heroes dedicated to killing me, nothing she could possibly do would be worse.
Garaki: Master, we've found your daughter. She joined a doomsday cult that wants to kill you and most of humanity.
All for One: …Teenagers.
#
Omake: In the Void
Yoichi: I feel sorry for my niece, but I'm struggling to connect with her. I just can't understand the mindless obedience, religious fanaticism, and attempted genocide.
Beros: To my last dying breath I will spite All for One.
Yoichi: Ah-ha! There's my genetics!
#
Omake: Epilogue
Flect Turn: Now that I'm in prison, I'm going to rethink my life. That bone-breaking kid made an interesting point about how I could have turned off my quirk if I'd tried harder. I could use this chance to turn over a new leaf and try to make up for my past wrongdoings. Orrrrrrr I could learn to control my cursed power better and try to genocide humanity again, but even better next time. Yeah, I prefer option two. Oh, look, someone is breaking me out of the prison van. It must be my loyal followers coming to save me.
All for One: Hi! I'm here to talk about you brainwashing my daughter, then ordering her to kill herself. Actually, it's going to be a very short chat. I'm going to express my feelings by breaking every last bone in your body, and you're going to scream.
#
Omake: Cult Rationalizations
Izuku: You hate people with quirks, how can I be your savior?
Beros: One for All is an exception because it is wielded by the Blessed Quirkless.
Izuku: I feel like that could just as easily make One for All into your ultimate abomination. Not all the past holders were quirkless. However I'm glad you landed on the delusion that won't lead to you trying to put an arrow through my skull.
Beros: Look, I just really want to kill my father.
Izuku: Relatable! If this AU isn't Dad for One, I probably got Deadbeat Abusive Hisashi as my father.
#
Omake: In Which Class 1-A Finds Izuku
Ochaco: I knew it would be difficult to bring Deku back but I didn't realize we'd fail this badly. (Looks around at the entire class lying prone with stun arrows sticking out of them.)
Katsuki: Is no one going to talk about the elephant in the room? Where did shitty Deku pick up a zombie archer?
Tenya: I feel the pet zombie must be in violation of class regulations if not international law.
Shouto: The bigger problem is that we seem to have been replaced by a zombie archer! Why does she get to follow him to hell when I can't? Just because she looks like a demon who already belongs in hell?
#
Omake: The Tragicomical Ending
Toshinori: All for One has been rewound to a child after he overused Eri's power, is it still ethical to kill him? I must conclude no.
Izuku: I just can't do it! I know he's All for One, but he's so tiny and cute!
All for One: Muhahaha! Because of your foolish sentimentality, I will return again. No matter how you imprison me, I will escape and—(Gurgles.)
Beros: (Pulls her knife out from All for One's throat) Savior, you told me that I should follow my own will from now on, so I decided I wanted to kill him.
Yoichi: That's my niece!
#This omake AU couldn't be Dad for One #Because that Izuku wouldn't have hesitated to kill his dad either #But he might have been persuaded to let his sister do it since she suffered more