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The Grand and Indestructible Demon King Hisashi, also known as All Hell in One, also known as the Terror of the Multiverse and the Dying of the Light, was late.
Sitting at an ebony table with legs craved from the skulls of his enemies, Hisashi glared at the dozen demon nobles gathered around him. The Duchess of Hell was covertly trying to stick a poisoned needle into the Baron of Hell while he gave a speech about her leviathans intruding on his lava lake. Deftly, Hisashi sent out a gust of wind to force her to drop the needle.
Some days, Hisashi felt like he was managing children, not the nobility of hell. Most days, actually. Hisashi’s beautiful queen and adorable son had left hell and moved to the mortal realm years ago. Inko had gotten tired of the perpetual assassination attempts, and Izuku had complained about how difficult it was to get hero merch in hell. Hisashi tried to visit his family as frequently as possible, but his work kept him busy. After missing ten family dinners in a row, he’d promised to be at this one. He’d sworn on his horns and tail. Inko was making hot pot with all his favorite ingredients.
But after eons of ignoring the problem, the Baron of Hell had chosen today to publicly file a claim against the Duchess of Hell. If Hisashi left, then he knew he’d come back to find them at war with each other. Then he would become even busier and have even less time to visit his family.
In his rage, Hisashi unleashed darkness that made the flesh crawl on everyone in the room. The baron ceased his unbearable yammer, his jaw slack and his forked tongue hanging out.
Hisashi growled, “I have a solution to this blessed problem that will satisfy everyone.” Everyone who mattered, in other words himself. “I’ll be taking control of this lake. Anyone who objects can face me on the dueling field—”
A glowing pentagram sprang up around Hisashi. Magic hummed through the air. He was being summoned, now of all times! Just when he’d been about to avert a war and see his family for the first time in months!
With one last scream of frustration, Demon King Hisashi was sucked into the portal.
Hisashi Shigaraki, also known as All for One, also known as the Dark Dealer and the Scourge of the Underworld, had spent years collecting the unholy instruments to summon the King of Hell. It had all started when he’d been ten years old, and some random jerk on Discord had told him that he couldn’t become a demon king when he grew up. Naturally he’d desired to prove that nameless fool wrong. Seeking out supposed demonic relics had been an idle hobby over his teenage years. It had briefly turned into an obsession after his brother died, when he’d desperately sought a way to resurrect Yoichi. Then Hisashi had mostly forgotten about his childhood quest until he coincidentally found an old book in a pawnshop he’d been burning down because the owner had an unpaid debt to him. Interestingly, he already had all the required instruments. He’d followed the ritual on a whim, not seriously expecting it to do anything.
The pentagram on the floor glowed. If this worked, then he was a genius and he’d known the book was real all along.
As the billowing sulfur cleared, Hisashi gazed at an exact replica of himself, except for the triangle-tipped tail and majestic ram’s horns. The demon king wore black armor and a flowing red cloak with spiky shoulder pads. A skull necklace hung around his throat. His black bat wings cast a giant shadow across the room. His eyes blazed crimson as if saturated with the blood of his foes. For some reason, they looked exactly alike. Even the expression on the demon’s face was oddly familiar to Hisashi, a hunger to hoard and consume (with a dash of annoyance at other people for existing).
Hisashi had assumed the demon king had taken on his own appearance to throw him off guard. But the demon said, “I’m going to rip out your spine and strangle you with it—oh, another me. A human, how repulsive. Please tell me that you’re at least a dark sorcerer.”
Caught up in the mood, Hisashi spoke the words he’d dreamed of since he’d been a ten-year-old boy: “Demon King, I challenge you for the throne of hell!”
The demon blinked. “Sure, the throne is all yours. Why not?” A malicious smile revealed his sharklike teeth. “I could use a break from the endless squabbles of the nobility and a chance to see my family.”
Hisashi narrowed his eyes. “It seems you don’t understand—”
“No, I understand perfectly. You want to be the demon king? Then you get all it entails.” The demon threw back his head and laughed with a cruelty that Hisashi envied. “I hope you enjoy the constant summons from teenagers trying to be edgy at slumber parties. I’m going home.” Then he vanished in a puff of sulfur. To Hisashi’s shock, the dark tendrils reached out and dragged him into the portal.
Freed of his responsibilities, Demon King Hisashi headed off to visit his lovely wife and son in their house in the human world. He was confident that he could take back his throne whenever he wanted it. In fact, he expected his human self would be begging him to return after a few council meetings. Sniffing the air, he picked up on the scent of his family and followed it.
However, the demon king hadn’t been home for so long that he ended up at the wrong house. Instead, he knocked on the door of the human Midoriyas—the wife and son of the villain All for One, not that they knew about the real profession of the absent so-called salaryman.
Izuku Midoriya opened the front door to find the absolute last person he would expect—his father. Most people would not consider their own dad to be a more novel sight than a salesperson or delivery man. But Hisashi Midoriya had been making excuses not to come home for years. Izuku gaped in shock, trying to figure out if this was a hologram. His father’s company developing new technology seemed more likely than his father taking a break from work. And for some reason, his father was dressed up in full demon king cosplay, including horns, wings, and a tail.
“My precious Izuku!” Hisashi swept Izuku up in a hug. His tail wagged. (Damn, that was a good cosplay.) “I’ve fought against the bureaucracy of hell to return in time for this family dinner. I found a loophole—some other sucker to take my place!”
“I’m glad your coworker could cover for you so you could take a vacation, Dad.” Izuku patted his father on the back. He felt annoyed there hadn’t been any advance notice for this visit, but not annoyed enough to speak up and ruin their ultra-rare family dinner. “Uh, what’s with the costume?”
“Oh, yes, I’d better get inside before the humans see.” Hisashi crossed the doorway, pausing to ruffle Izuku’s curls. “You’re so cautious, hiding your horns and tail even at home.”
Inko stepped into the hallway, then double-took. “Hisashi! You…I thought you were at work…”
Hisashi beamed. (Was he using fake teeth? They looked very real and sharp.) “I’m taking a nice, long vacation. I might even be here for centuries, depending on how long the idiot human lives.”
Inko’s forehead wrinkled as she tried to process this. “Oh, you and your jokes. I was making udon, but I think I can stretch it for more people.”
“No hot pot?” Hisashi’s pointed ears drooped. “I understand, you’re annoyed at me for being so late. Yoichi will be angry, too. Is he here?” Hisashi swept down the hallway, calling Yoichi’s name.
Izuku and Inko stared at each other. Worriedly, Izuku said, “He’s talking like my uncle is alive again.”
Inko shrugged. “You know he does that sometimes. He never properly processed his brother’s death, I fear.” Hisashi went through phases where he either intensely grieved his younger brother or acted like he’d never died.
“And that cosplay…”
“Well, you know your father has always been a bit of a chuunibyou.”
That was true. It wasn’t even the first time that Hisashi Midoriya had cosplayed as a demon king at the dining room table. Last time he’d gotten annoyed at both Inko and Izuku dressing up in All Might onesies so he’d put on his own demon costume claiming that evil felt underrepresented in their house. The costume was especially good this time but otherwise this was fairly normal behavior.
Izuku pushed away his doubts and went to set the dining room table.
“This udon tastes amazing,” Hisashi said, licking his lips. “Did you flavor it with damned souls?”
Inko laughed. “No, that’s just paprika.”
Izuku raised an eyebrow. His dad was really committed to the chuunibyou act today. It was almost enough to make Izuku wonder if his father had been sent home on medical leave. But the one time Izuku had met one of his father’s employees, the giant man had been just as dramatic. The giant had cried a lot and called Izuku a little lord. Izuku had concluded that his father’s office must be full of people as eccentric as him.
Hisashi balanced a fish cake between his chopsticks, eyeing the spiral design on front. “You even added the symbol of the underworld. How considerate of you, love.”
“I got those at the grocery store,” Inko said.
After slurping up his last bite, Hisashi patted his stomach. “Ah, now that was a meal fit for the Lord of the Underworld.” This was also not unusual, as Hisashi regularly referred to himself as the Lord of the Underworld. Inko said he had a high school sense of humor.
Izuku ate the fish cake he’d been saving for last. “Delicious, Mom.”
“Thank you.” Inko beamed. “We can have the hot pot you were craving tomorrow, dear.”
Hisashi sighed. “I need to kill more of my annoying underlings who are responsible for delaying me and making me miss your lovely meals.”
Izuku laughed. Yup, his dad was the same as ever! He said that every single time he came home.
“It’s just a shame that Yoichi couldn’t be here,” Hisashi said. “Should we save a bowl for him?”
“Sure, we can offer it at the family shrine,” Inko said.
Hisashi’s forehead wrinkled. Then he laughed. “Ah, you joke, my love. As if the Lord of the Underworld would have an altar!”
Inko laughed. “You’re very committed to that cosplay!”
“You already told that joke, Dad,” Izuku grumbled. “Get over yourself, Lord of Salarymen.”
“Joke? Who but the Lord of the Underworld could produce the cursed and all-consuming flame of hell?” Hisashi spat forth a tongue of red fire. It was tiny yet the heat hit Izuku like a wave.
Izuku said, “Yeah, yeah, we know that you have a Fire Breath quirk.” He gathered his dishes.
“How odd, why don’t you use magic to dispose of those?” Hisashi asked. “It’s beneath a prince to do menial labor.”
Izuku carried the dishes to the sink. “Magic? Is that your excuse for getting out of washing the dishes? Mom cooked, so we clean. It’s only fair.”
Hisashi followed his son into the kitchen. “Ah, I see! You want to clean together as a bonding activity. How quaint. I suppose sometimes it’s amusing to go without the servants. Yes, it warms my shriveled heart that you desire so greatly to spend time with your old man.”
Izuku handed Hisashi a pair of dishwashing gloves. “Less monologuing, more cleaning. We need to finish quickly. A hero merch store downtown is having a clearance sale, and I need to get over before all the good stuff is gone.”
In a dining room on the other side of the city, Demon Queen Inko turned off the heat under her hotpot. “I suppose at this point, there’s no chance of your father showing up.”
“His loss,” Prince of Hell Yoichi said, dabbing at his lip with a napkin.
Crown Prince of Hell Izuku shrugged. “Dad must have gotten caught up at work again. It’s far from the first promise he’s broken.”
A sour mood fell over the room. Yoichi sprang to his feet. “I’m going to find my brother and beat some sense into him! How dare he neglect my wonderful sister-in-law and my adorable nephew?” With a yellow cloud of sulfur, he vanished.
Izuku asked, “Mom, want me to overthrow Dad and become the new King of Hell so he shows up for dinner on time?”
“Aw, you’re such a good son.” Inko mussed her son’s curls around his small, pointed horns. “But then you’d have to deal with hell’s bureaucracy instead.”
“True.” Izuku sighed, exhaling a puff of smoke.
“I know what will cheer you up.” Inko clapped her hands. “All Might merch! Let’s go out shopping. I saw a flyer for a clearance sale today.”
As soon as the human Hisashi appeared, a crowd of demons dropped to their knees and intoned, “We are at your service, All Hell in One.”
Hisashi glanced around. This room looked exactly as extra as all his demon king fantasies, from the molten lake of lava running around the stone floor to the candelabras with black wings hanging around the medieval-style room. Red banners with demonic faces decorated the walls. The smooth granite table had a single chair different from the rest: a throne with arching, razor-sharp horns on the back.
A demon who looked oddly like Tomura turned to the others and said, “Dismissed.” They filed out of the room. Demon-Tomura said, “I see you’re still in your human form after visiting your family. Did you have a good dinner?”
Hisashi blinked. He’d assumed the demon king had taken on his form as a ploy to unnerve him, but did they just coincidentally look exactly alike? That was convenient. It would make his takeover easier. “Yes, of course. What is on my schedule today? Torturing damned souls? Slaughtering armies?”
Tomura placed down a massive pile of papers on the table. “Paperwork. You declared you would take over the Eastern Lava Lake, so you need to fill out all of these forms. In order to prevent a civil war from breaking out, you must finish by the end of today.”
Hisashi gazed down in horror. He’d become a villain so he didn’t need to bother with rules and paperwork. “All of this in one day?”
“Of course not!” Tomura laughed. “That would be way too little paperwork for one day. You also need to fill out the usual forms related to hell’s maintenance.” With a snap of his fingers, he materialized three more stacks equally large. “Good luck! You probably shouldn’t have put all of this off until the end of the day. Oh, by the way, Her Majesty the Demon Queen gave me permission to lock you into your meeting room whenever you don’t complete your paperwork on time.” Tomura vanished, and the door took on a glowing red light.
Alone in the strange room, Hisashi tried the door handle. “Ow!” An electric spark danced down his hand. He shook it out. Next he tried using a quirk to smash the door, but that bounced off too. The impact sent him reeling backward.
It appeared there was no way out except to finish the paperwork. This was why the Demon King had happily ditched his job! Because it was way more boring than being a villain! What a scam.
Could he even read the demonic language? Hisashi picked up a piece of paper. It was covered with strange runes, but as soon as he touched it, the letters changed to Japanese. That sure was convenient. Oh, the page was still changing. A black mouth formed on the bottom near the signature line, then bit Hisashi’s hand.
“AHHHHHHHH!” Hisashi screamed, hopping up and down. Neither fire nor water quirks could damage the paper. Eventually he managed to rip it off and threw it against the wall. Panting, he nursed the cut on his hand. “No wonder people say to never meet your heroes. Being a demon king is no fun!”
The scent of sulfur filled the room, followed by a pop of displaced air. Yoichi stood with his hands on his hips, looking as young as the day he’d died—except this Yoichi had white leathery wings and curly horns. Hands on his hips, he demanded, “Big brother, how could you miss Inko’s delicious hotpot? She even brought all your favorite ingredients.”
“Y-Yoichi.” Hisashi stretched out a trembling hand to touch the pale cheek. “L-little brother…you’re alive…”
“Don’t kill me off—ow!” Yoichi squawked as he was dragged into a hug. “What’s wrong with you? Why do you look like a human even in the palace?”
Hisashi sobbed as he hadn’t since he’d been a small child. “I don’t care if you’re an illusion or from a parallel universe, I’m still keeping you! I’m never letting you go again!” His grip tightened.
“My ribs!” Yoichi screamed. “Along with your horns, it appears you’ve completely lost your mind.” He squirmed free, then ran for the door. When his hand touched the knob, the red lighting attacked him. “Blessings! Who sealed this door?” His face paled. “Why can’t I teleport out?”
“Hehe…you’re never leaving me again, my dear little brother.” Hisashi grabbed his brother from behind with a death grip. “It appears that both of us are trapped in here until all of the paperwork is finished. How kind of you to volunteer to help me!”
Yoichi’s tragic scream echoed around the castle.
Standing before a display table, Izuku sorted through the hero merchandise with lightning-fast hands. As he’d feared, this failing store had nothing except junk. It hurt his heart to criticize any hero merchandise. All of it might be loved by someone. But as Izuku picked up a Hawks figurine with blue wings and half the hair falling off, he was hard-pressed to call it anything except junk. Sometimes these types of sales had rare treasures. But it appeared he’d wasted his and his parents’ time. What a waste, to come here on a rare day when his dad was home.
“Nothing good?” a voice asked from behind him.
Turning around, Izuku saw a boy who looked exactly like himself—except for his demonic horns, wings, and tail. He was even dressed like a medieval prince in a green velvet doublet. “Huh, nice cosplay.”
The demon boy laughed. “I love attending hero events because I can have my horns out. Hmm, you look a lot like me.”
“We do look alike.” Izuku scratched his head awkwardly. He wondered what his parents would think. Inko and Hisashi were currently in line at the café in the front of the store, buying coffee. “I guess everyone has at least one doppelgänger.”
“One per universe,” his double murmured, looking amused. “Are you a hero fan, too?”
“Of course! My favorite is—” Both of them spoke together: “All Might!”
His double pulled open his old-fashioned jacket to reveal the shirt underneath. “Check it out.” His T-shirt showed a yellow All Might with demonic horns instead of hair tufts. “I designed it myself.”
“Oooo, that’s a new one,” Izuku said. Any new All Might design deserved to be appreciated. “Here, look at my phone background.”
His double peered at the picture. “You made a collage of All Might stats! Impressive. Have you seen any good All Might merch here?”
Izuku shook his head. “Nothing I don’t already own.” They both sighed.
“I swear, this store is clearly second-rate since they don’t have much All Might merch.” His double wrinkled his nose. “Would you believe I’ve seen more Endeavor merch?”
“I know, right? All Might is the number one hero!” Izuku’s gaze fell on a hint of yellow buried in the pile. He pushed away a Miruko plushie to reveal an All Might keychain. At first glance it appeared to just show the standard plastic All Might head, but one of the hero’s bobbly eyes was missing.
His double gasped. “Is that the legendary one-eyed All Might keychain? I must have it!”
“The eye was missing due to a production error. Only a hundred keychains were made before they caught the mistake and stopped production.” The keychain was worth enough money to buy a mansion, although of course no true fan would ever sell it. Izuku felt faint. His hand shot forward.
His double’s hand moved at the same time. Both of them fastened on opposite hair tufts. They froze, unwilling to tug for fear of damaging the priceless treasure.
An overly friendly smile on his face, Izuku said, “Excuse me, I believe I saw that first.”
“I called dibs on it first.” His double didn’t budge.
“My hand touched it first.”
“No, I believe my hand touched it first.”
Izuku did a mental calculation of his allowance. His father had been very, very generous and could be persuaded to part with more money when guilted about his frequent absences. “I’d be willing to pay you double the market value of the keychain to give up your claim.”
His double glared. “There’s no need for insults. We both know a true fan wouldn’t let go of such rare merch for any price.”
“True. My apologies.” Even as Izuku spoke, his hand grabbed the edge of the table, jerking it toward him.
His double fell forward, but did not release the keychain. “I see you’ve declared war, mortal!” His jaw opened to an unnaturally wide degree, revealing rows and rows of sharp teeth. The double bit down on Izuku’s arm.
Despite the sparks of pain dancing behind his eyes, Izuku maintained his death grip on the keychain. He bit his double’s arm back.
His double howled but did not release his alligator jaw.
“Izuku, what are you…?” Hisashi stepped forward, holding a cup of coffee. His eyes darted between them. “Two…Izukus? Stop that!” Leaping forward, he wrenched the boys apart with unnatural strength.
Blood on his mouth, Izuku wailed in protest as the priceless keychain hit the floor. His double cried out, too. Hisashi held them both in place.
Light flowed from Hisashi’s hands, and both boys’ injuries healed. His gaze became sheepish. “Sweet blessings. I went to the wrong house, didn’t I?”
The double dangled in the air from the back of his coat like a kitten in an adult’s mouth. He glared. “You missed our family dinner, Dad.”
Hisashi protested, “I went to the other Izuku’s dinner! You tell him, Human Izuku.” He shook Izuku.
The double glared harder. “Do you think it helps your case that you can’t even tell me apart from my alternate universe world self?” Even as he spoke, he kept reaching for the keychain. Determined not to be outdone, Izuku struggled harder. It appeared the guy holding him might not be his dad or even from his universe, but he didn’t care. Whatever these two were talking about mattered way less than the keychain.
Demon Hisashi sighed. “Boys, there is no need to fight.” Magically, the keychain floated in the air, then duplicated. “See? One for each of you.” Demon Hisashi set them down on the table.
Izuku’s gaze locked on the prize. Naturally, a thought crossed his mind: the only thing better than one ultra-rare All Might keychain would be two ultra-rare All Might keychains.
Any fan would think the same thing. Naturally, his demonic double lunged at the same time he did. With two hands, each of them grabbed both keychains. Then they froze, unwilling to yank for fear of damaging the merch.
“I’ll drop the left one if you drop the right,” Izuku offered.
“Sure. You go first.” His double’s eyes narrowed. They looked deep into each other’s eyes. Neither moved.
Demon Hisashi flicked a tear of joy from his eye. “You’re both so greedy, I feel proud. Hmm, I can’t help noticing that my human self ran off to hell and left his family unprotected. Clearly I should claim them as my own. Two Izukus would be better than one!” He advanced, eyes gleaming and claws out.
“Not so fast!” Human Hisashi and Demon Yoichi appeared in a flash of light. Snarling, human Hisashi cried, “How dare you try to steal my son?”
Demon Yoichi said, “Big brother, I’ll never complain about you and your workaholic lifestyle again, just get rid of this one and come back. He scares me.” Yoichi tugged at the human’s hand gripping him by the horn. “Ugh, I would rip you to shreds if my body wasn’t too weak from all that paperwork.”
Human Hisashi laughed manically. “You tried to trick me into your godawful job, but I’ve escaped!”
Demon Hisashi said, “I didn’t trick you—you volunteered. No take-backs. Hell is all yours. I’m staying on earth with my family…both of them.”
“Like hell you are!” Human Hisashi snarled. “I’ve stolen your brother!” He did not notice that Yoichi had replaced his horn with a plastic replica of Mount Lady’s purple horn. Yoichi tucked an Izuku under each arm, then ran away. The Izukus remained frozen, holding the keychains and locked in their merch standoff.
“I’m sending you back to hell, then both Izukus will belong to me.” Demon Hisashi laughed manically. Flame poured from his mouth. The human met this with a shield of water. The back wall of the store blew out as they clashed.
In the café, Demon Inko and Human Inko sat across from each other, drinking coffee.
Demon Inko said, “I must get your udon recipe, since my husband enjoyed it.”
“Of course. I’m sorry for that silly misunderstanding,” Human Inko said.
“No, it’s all my husband’s fault for shafting his work off on someone else,” Demon Inko said.
Fragments of wood flew past them as the store wall exploded. Then Yoichi ran by, holding two Izukus.
Demon Inko sighed. “I suppose we’ll need to straighten out this mess.”
Human Inko reached into her purse. “I brought my slipper.”
OMAKE TIME!
Omake: Battle of the Jaws
Demon Izuku: No human could bite like that! What are you? An alligator mutant?
Human Izuku: I’m a hero fanboy!
#
Omake: The Nightmare Solution
Human Hisashi: Jeez, the demon nobles have the mentality of high school bullies and generate the same amount of drama.
Demon Hisashi: It’s a hell of a job, literally.
Human Hisashi: We have horrible bureaucrats in my world, too. Hmm. If I sell you the HPSC president then we could her the new Queen of Hell while we play around?
Demon Hisashi: I do not know this HPSC you speak of, but it sounds entertaining!
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Omake: The Impossible Dilemma
Human Hisashi: Unlike my idiot double, I can definitely tell my son apart from a demon.
Demon Hisashi: My Izuku can disguise his horns and wings.
Human Hisashi: Oh, no, I’m in trouble. Quick, which one is trying to steal All Might merch? No, that’s both of them. Which one is trying to bite me? Nope, still both of them!
#
Omake: The Moms Do Not Feel the Need to Interfere with the Biting
Demon Inko: My son is going through a special phase in every demonic child’s life…patricide.
Human Inko: It’s so moving how our sons can put aside their bitter and often bloody rivalry over All Might merch when it’s time to hurt their dads!