Author's Note: This story is part of a series starting with "The Peculiarities of Izuku Midoriya." Friday the 13th in October seemed like the perfect day to bring back Haunted One for All! Though this fic is short, I have two more planned for the series, to be posted over the next couple weeks.

This whole series takes place in an alternate universe, so assume the butterfly effect caused Mirio and Izuku to confront Overhaul together during the raid on the Shie Hassaikai.

One second after Nemoto fired a quirk-erasing bullet, Mirio threw his body on top of Eri. Two seconds later, Izuku burst through the wall and jumped between both of them and the gun. The bullet hit his leg. He looked down, seeming briefly stunned at the sight of blood mingling with the green sparks running down his body.

Mirio made a pained sound in the back of his throat, as if he'd been the one struck. Eri did not make any sound at all. She could not bring herself to feel surprised. Deep down, she'd known it would end like this. That was why she'd walked away from these two boys when she'd first met them, fully aware it would end in both of their dooms if she dared ask for help. Heroes were not real. The world had only monsters like Overhaul—and her.

Overhaul laughed harshly, discordant as a train rattling over rusty tracks. "It's funny how the power of the girl you're trying to save has robbed you—"

"Shut up." Izuku swayed, clutching his head. The light running down his leg plugged the bleeding. As he turned his head toward the villains, his eyes glowed toxic green. "Oh, I didn't mean you, though you should shut up too."

An immense, heavy pressure filled the room. At first Eri believed she'd imagined it, but then the spikes littering the floor started to shake and crumble. The air became darker and denser. Chronostasis and Nemoto both fell over, bleeding from their noses and mouths. Mirio's eyes rolled back in his head. Though he'd passed out standing upright, he still clutched Eri close to his chest.

Strangely, Eri herself did not have any trouble staying awake. It was only pain, not real damage to her body. Eri had endured invisible pain so frequently that she could shove it away into a box inside her head and just not think about it.

Izuku twitched like a puppet hanging on slack strings. Blackness exploded from his body: dark clouds and tendrils like whips. The debris lifted off the floor and orbited around him in a swirl. The green glow was so blinding, Eri could no longer look directly at him.

Using several new spikes, Overhaul caught himself before he fell. Furious growls came from his mouth. The blood dripping from his nose kept vanishing. Clearly he was using his power to heal himself, but taking new damage almost as fast. He screamed, "Impossible! The bullet should have erased your quirk, not given you half a dozen more!" His eyes sought out Eri through the swirling dust as if expecting her to have answers, but she knew nothing. How amazing, to see the man who'd tormented her looking frightened and confused, all his confidence and control stripped away.

Izuku moved so fast he seemed to teleport, landing on a spike in an animalistic crouch. He leaned down, peering at Overhaul so close their noses nearly touched. "You spoke of robbing me?" His voice took on an echo, eight or nine voices layered on top of each other. "Impossible! All for One himself could not steal us! We are the eternal quirk. We have existed before you were born and we will endure after your bones decay to dust." Izuku tilted his head at an unnatural angle like an owl. "A day which may come soon." Howling, swirling colorful shadows rose up around him, flashing green, blue, red, white, orange, purple, pink, and blazingly gold. Stretching out one hand, Izuku flicked Overhaul on the forehead.

The yakuza went through the wall, then the next wall, then the next. His scream faded into the distance, finally cutting off as rubble fell on top of him.

Izuku leapt to the ground and walked back. His eyes, now a normal green, widened on seeing Mirio fall over. "Oh, no! Sorry, that was too much." He propped Mirio up against the wall and checked Eri over. "Are you hurt? I'm very sorry. I told them to stop doing that or at least give me more warning to evacuate people. If you're bleeding, then they'll get no new comic books for a week."

"I'm fine," Eri chirped, determined not to get her new favorite ghosts into trouble. "I didn't feel a thing."

"Overhaul can't hurt you any longer. He's…probably not dead. He seemed tough, right?" Izuku's brows drew together. "Oh dear, Mr. Aizawa is going to be furious if I've killed Overhaul. Heroes aren't supposed to do that."

"You're my favorite hero," Eri told him, and extended her arms to let him pick her up. As she touched him, she healed the bullet injury. She wasn't afraid to use her power on him, because she knew his quirk would stop her from hurting him. She could feel it swirling beneath his skin, a deep bottomless well of power.

Eri slept peacefully that night. She knew she was not a monster because she'd met a real monster (and he was cool so apparently monsters weren't so bad.)

OMAKE TIME!

Omake: Mirio Reacts

Mirio: I'm so happy I turned down that quirk.

Eri: What?

Mirio: I mean, I'm so happy that I still have my quirk. (Not that one.)

#

Omake: Detention for Problem Child

Nezu: Midoriya fought against Overhaul—

Aizawa: No, he didn't, he was with me the whole time. Someone else must have killed Overhaul. Or maybe he tripped on one of his own spikes.

Nezu: I appreciated your loyalty and willingness to commit perjury for your students, but Overhaul isn't dead, just in a coma.

Aizawa: Let's wait and see if the yakuza pulls through before I change my story.

#

Omake: Sir Nighteye Did Not See It Coming

Izuku: The future can be changed! Sir Nighteye is still alive!

Sir Nighteye: Overhaul landed on my head.

Izuku: I did say I was sorry about that. My quirk is sorry, too. Everyone, stop glaring and apologize. They didn't do it on-purpose—you did? Well, I didn't do it on-purpose. In fact I'm grateful to you for cushioning Overhaul's fall and saving my hero career.

#

Omake: A Less Eldritch Explanation for One for All's Survival

Yoichi: We've been hit with a quirk-erasing bullet. One of us must sacrifice their quirk so the rest of the power stored inside One for All can survive.

Banjo: Not it. My quirk is the best. Everyone loves Black Whip.

En: My Smokescreen is versatile and useful. Nana, what if we give up Float? All Might could already leap between tall buildings with the strength stockpile, so it's redundant.

Nana: Excuse me? Float is not redundant! Without my power, we couldn't terrify the living with our eldritch levitation.

Second: Fa Jin is basically a useless ability. It just does the same thing One for All always did.

Third: Leader, you traitor! Shouldn't the captain of the ship volunteer to sacrifice his quirk first? You're always going on about how yours too dangerous to use.

Banjo: Second makes a good point. All in favor of sacrificing Fa Jin, raise your hands. (Raises all of his tentacles.)

Hikage: I volunteer to eliminate my quirk because I've always hated it.

Yoichi: Everyone, I have a far better idea. Let's ditch my ability to pass on quirks. Ninth keeps threatening to give us away. Now he'll be stuck with us forever! Hey Ninth, good news, we can never, ever leave you.

Izuku: NOOOOOOOOOOOOOOOOOOOOO! (Murders Overhaul, Chronostasis, and Nemoto in a feral rage.)

Yoichi: I think he took that relatively well.

Author's Note: FYI, my fics have been taking a while to show up on this website after I post them and the subscriber emails are not going out. But the fics seem to appear under my profile in a day or so. I believe this is a site-wide issue.

Also, I'm hosting a fanfic writing/art contest called Three Weeks of Trioholders. Check out the details on my tumblr:
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