Author's Note: It's been a while since I've inflicted All for One on Izuku too in this series. Thank you to Gfan97 for this cool idea and writing omakes with me.

Izuku raised his fists and readied for battle. Gentle Criminal and La Brava would be tough opponents. However, he would stop them from disrupting the Cultural Festival no matter what, for the sake of Eri's smile.

Instead of attacking him, La Brava leapt forward, threw her arms around his neck, and squealed, "It's great to finally meet my darling's little brother."

Izuku was so surprised, he froze up. As a hero, he could hardly attack someone who wasn't trying to fight back. His arms went up to return the hug by habit. He looked at Gentle Criminal, who was scowling and fuming. Finally Izuku asked, "Aren't you too old to be my brother?"

Crossing his arms, Gentle Criminal growled, "I'm only thirty-two. That's not an impossible age gap even if our father wasn't an unusual case. My hair is naturally white like Dad. I drew eyebags under my eyes to match my dear assistant. I'm not old!"

Even more confused, Izuku asked, "Isn't thirty-two already ancient?"

"No wonder older brothers want to vault the younger ones. It's on now, you cocky teenager!" Gentle Criminal lunged. "Today I'll finally prove that I'm better than you at rebelling against our dad."

Izuku sidestepped. Gentle Criminal nearly fell over but caught himself. He came up swinging, but realized he couldn't punch Izuku without hitting La Brava who was still hanging around his neck. Screeching to a halt with fist raised, he glared.

Izuku said, "I don't know what kind of misunderstanding this is or if we're actually related." Though this weirdo's hair and tendency toward dramatics was starting to jog his memories of his long-vanished father. "But I didn't become a hero to rebel against anyone. It's been my dream ever since I was a small child. It has nothing to do with my father."

"Easy for you to say!" Gentle Criminal shouted. "You're the child who our father loved and stuck around to raise. He dated my mother only because she was a descendant of the Peerless Thief, then left her as soon as she got pregnant. He wouldn't even pay off my high school debt because he said it would teach me a lesson about helping people."

"I'm increasingly convinced that you have the wrong person." Izuku finally disentangled La Brava from his neck and set her down. "My father is a deadbeat too. He ran off to America to get the milk when I was still in elementary school. I haven't seen his face in years."

Gentle Criminal's jaw dropped. "All for One abandoned you, too? Jeez, he really is the worst dad."

"We should beat him up next," La Brava said cheerfully. "It will be a family bonding activity. I believe my darling can do anything."

"ALL FOR ONE?" Izuku shrieked. "No way, not my father."

"You didn't know? I'm sorry." Gentle Criminal did look sincerely sorry to deliver such bad news.

"YOU DON'T NEED TO APOLOGIZE BECAUSE HE'S NOT MY FATHER."

"You look just like him."

"I don't look like a potato!"

"Before he lost his face, of course. You have the same mannerisms. You get the same look on your face when you see a cool quirk. And I saw you use multiple quirks."

"That's—" Izuku stopped talking before he gave away the secret of One for All. Unfortunately, memory had come back to him. Flashes of his father's tall figure in childhood with curly white hair. The voice he'd heard over the telephone since the transfer to America. The voice that sounded suspiciously like the mysterious villain at Kamino. At this point Izuku went into frantic denial. "Whoa, it's absolutely awful that you got All for One as a father. You should speak to a psychiatrist about it. Even your daddy issues must have daddy issues. But this has nothing to do with me. My father is an ordinary businessman working abroad. You know what? There's free psychiatric services in jail. I could take you there."

Gentle Criminal didn't seem to be listening. "I suppose there's no point in competing with you when our dad ditched both of us."

Izuku eagerly jumped on the excuse. "Yes! Please leave! You see, there's a young girl named Eri who is like a little sister to me. I want to make her smile at the Cultural Festival because—"

La Brava leapt up in the air and shouted, "Let's compete for the title of who can be the best older sibling to this Eri instead."

"Excellent idea," Gentle Criminal said. "This is why I want to vault you, my darling."

La Brava giggled. "You express your love in such odd ways. I'm into it."

Gentle Criminal pointed at Izuku. "I'm going to take your place as Eri's favorite brother." Then he shot off.

Izuku chased after, screaming, "Get back here! I told you that I won't let you disrupt the festival."

When Izuku finally caught up with the two villains, he feared the worst: the festival disrupted or even shut down.

Instead, Gentle Criminal and La Brava sat on a bench next to Eri, offering her adorable old-fashioned clothing and…a real sword?!

"I've always wanted a sword." Eri giggled as she tested the weight. "But Izuku is still my favorite because he beat Overhaul into the ground."

"I could do that too," Gentle Criminal insisted, leaping up. "Come, La Brava, let's go find a yakuza and make him suffer even more."

Izuku considered calling someone to arrest Gentle Criminal and La Brava. He weighed the risks of interacting with them again and learning more than he wanted to know about his father. He decided that he couldn't possibly interrupt Eri while she was smiling.

OMAKE TIME!

All for One: I can't believe my idiot oldest son became an influencer instead of getting a real job. At least I still have Tomura.

Tomura: I want to be a NEET.

All for One: At least I still have Izuku.

Izuku: I'm the Ninth successor of One for All.

#

Shouto: Your father is terrible and your brother is a villain who broadcasts your family fights on social media? Whoa, we have a lot in common. My big brother is better at villainy though.

Izuku: Dabi is not better than Gentle Criminal. He's just mooching off his team! Whoa, is this what the sibling instinct feels like?

Shouto: Yup, it compels you to defend them against everyone else even when you hate them. I guess you two must be related after all.

Izuku: I need to tell Gentle Criminal the good news: his father is actually a businessman not All for One.

Shouto: And there's the denial that often follows.

#

Izuku: Isn't thirty-two already ancient?

Aizawa: EXCUSE ME?! I'm expelling you.

#

Yoichi: My oldest nephew is too villainous.

All for One: He's not evil enough.

Gentle Criminal: I don't care what either of you think because I only admire the Peerless Thief. Dad's just mad that I've publicly beaten up more heroes than him.

Peerless Thief: I'm mad because All for One's son is a better successor for me than Mr. Compress. At least he has coherent goals.

#

Yoichi: I know how difficult it can be to have a villain older brother.

Izuku: I don't have an older brother.

Yoichi: That's the spirit!

#

Gentle Criminal: Since Izuku got himself unofficially adopted by All Might, I'm going to find an even better hero to be my new dad.

Gang Orca: Who are you?

Gentle Criminal: He loves me already.