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A Deal with the Deku

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Izuku has been pushed down for as long as he’s been alive. To be fair, he is six years old, so he really hasn’t been alive for very long, but it’s true, just the same. It’s been two years since he was diagnosed as Quirkless and it’s been one since Kacchan turned on him. It’s been six months since Kacchan started beating him up and it’s been exactly five minutes since the last time he did.

Brushing some of the dust and dirt off his pants and shirt, he grabs his bag from under the slide - he’s been hiding it there since Kacchan almost set his bag on fire - and swings it over his shoulders. He slinks out of the playground and the clock outside the nearby café reads 4:30 back at him. His mom must be really worried about him, even though their school is a block from their house. 

(He wanted to ask her to pick him up so he wouldn’t be bullied anymore, but he knows she’s busy. She does have to take care of him, after all. Deku, useless Deku, eating her food and being a waste of space. She never does, calling it a waste of time, but Izuku knows she loves him. She loves him, right?)

In his daze, he forgets to turn when he reaches his street and he continues to walk. Store after store, street after street, block after block, he walks and walks until he can’t walk anymore. He has no clue where he is, so he glances around at his surroundings. He’s at a garbage dump and there’s a sign to his right that says where he is. He squints at it, trying to read the original writing under the graffiti over it. Da-dagoba? Dagobah Beach?

The graffiti reads a few words he doesn’t understand, along with a few he does. He’s not sure why the sign is telling him to go away and beware, but he ignores it. For the other words, he tries to spell out but his mouth seems not to want to cooperate. They look like gibberish to him, a nonsensical mix of consonants with no vowels. They don’t look like words to him, so he concludes that they’re probably a different language, like French? German?

He shakes off the eerie feeling that the weird language instilled in him, and he looks back at the mess in front of him. This is a beach?

Izuku walks to the first mountain of garbage, the one nearest to the entrance. He wades through the trash, not having anything else to do. He’s lost, he’ll admit that, but maybe there’s something of value here. Something that’ll prove that he’s not worthless, that Deku’s not worthless. Grabbing anything that his little hands can hold onto, he pushes the garbage to the side, slowly but surely making a dent in the mound. Covered in small cuts from the sharp objects that he’s picked up, his hands drip blood onto the rusty metal, but he feels no pain. 

The only thoughts going through his head right now are bitter ones. “I need to be useful. I need to be useful, useful, not useless, not Deku.” 

The sun starts to set around him and he’s starting to feel the blood loss, with the cuts now extending up to his elbows. By now, his t-shirt is torn up into little pieces, the sleeves having as many cuts and tears as his arms currently do. The wounds burn and a small part of him wonders if this is how he dies. Dead in a trash heap. Just like how a Deku should be. Is this where he belongs?

(A bigger part of him whispers that he should just stay here, that he should relieve Mama of the burden he puts on her. He’s not useful, he doesn’t have a Quirk.)

He reaches the sand, having torn the trash mountain in two from the top. It wasn’t very high to begin with, but as his feet touch the sand, he lets out a breath he didn’t know he was holding. He plops down on the beach, grabbing a handful of sand and watching the individual grains seep through the cracks in his hands. The cuts in his palms leave the sand speckled with blood and from the speed at which he’s bleeding, he’s fairly sure he’s cut an artery.

He kicks his legs out to relax and very nearly almost screams in pain when his shoes make contact with a hard object. (Thankfully, the object wasn’t sharp, or else he wouldn’t have feet anymore.) He sticks his arm out and grabs the object that almost broke his foot. It’s an ornate box, as black as the night itself. There’s a lock on the box, but it seems like it’s been worn down from the elements and just from time itself, if the snapped shackle is any indication of such.

This is worth something, right? He picks it up and when he turns it upside down to see the bottom, a small black book falls out. The book is as pitch black as the box it came in, with certain pages sticking in and out, special small tags attached to three pages. 

He turns to the first marked page, only a few pages from the beginning. He feels the temperature around him fall by a few degrees, but he chalks it up to the sun setting. It’s written in the same type of gibberish as the words on the sign were and it’s illegible to him, so he turns to the next marked page.

This page, unlike the first one, is relatively deep into the book. There’s no writing on this page, but it’s covered in squiggles and drawings, all of one person. Well, Izuku thinks it’s a person. The man has two horns protruding from his head and claws on his hands. A barbed tail sweeps behind him and there’s a pair of wings stretching from his back. There are two drawings of the man: one in good lighting, where the man is seen with ruby red skin, and another in darkness, with the eyes and grin being the only noticeable things. He looks familiar and Izuku stares at the picture for a while, wondering where he’s seen this man before.

The last marked page is the last page in the entire book and Izuku notes that there’s a page number in the bottom corner. It reads ‘666’ back at him and this page is covered in a glossy sheen, compared to the worn and tattered paper the rest of the book is made of. This page is written in Japanese, and Izuku looks through the paragraph. 


To whomever this may concern, if you wish for power and revenge, there is a way for you. Ever felt like you’ve been betrayed? That you’ve been written off? That you’ve been beaten into the ground, your hopes and dreams crushed? Only I, and this book can save you. All others have lost hope in you, haven’t they? And why blame them? You’re useless, weak, a sinner, impure. Why would angels stop to help you? They are free and good. You are not .

(As the paragraph goes on, Izuku finds himself nodding, first in determination, then in resignation. Why would they help him? They have Quirks and are strong. Why would they help a useless Deku, like him?)

Draw this sigil, this pentagram in your own blood and you will find what you desire. 


There’s another sentence under the writing, but it’s written in the same scrawl and language as the other text, so Izuku disregards it.

Izuku looks at the book, then at his bleeding hands, then back at the book. Can’t hurt to try, right?

He flattens the sand around him, careful not to bump into any of the garbage, lest it all fall on top of him. He draws out where blood is supposed to be in the sand, and his cuts leave a small trail of blood where he puts his hands down. He grabs the previous bloody sand and sprawls it out in the design, reducing the amount of blood he needs. He’s not sure if it needs to be fresh, but he thinks it’ll be fine.

As he’s about to finish the final line, he steps back to look at the sigil. It’s a wide circle, with a five point star drawn inside. He drips the last line together and as soon as the star is intact, it lights up a vibrant red. Izuku sways where he stands, partly from the energy coming from the circle, but mostly from the blood loss.

Sorry Mom, I don’t think I’ll make it back. It was nice while it lasted, wasn’t it? Don’t miss me.

The last thing he sees before passing out is a tall man with a maroon cape rising out of the red light, before rushing to his side. It’s funny that only at death’s door, does someone actually care for him.




You’ll just be returning to me. You’ll be coming home. You belong where I am, where no light reaches. You belong in Hell. You’ll join your friends, you will, YOU WILL. After all, nobody cares for you like I do. Nobody loves you like I do. Nobody will give up anything for you, not like I do. I am your only, so you must be my only. You must be mine, and mine alone. So you must kill for me.

- Final words on Page 666 of Izuku’s Shadow Booklet , written in a mysterious language.




Mephistopheles didn’t expect to be called to the surface world. He’d told his previous owner to throw his box into the sea, so he’d never have to corrupt another soul again. He’s made the same mistake by selling his own soul to the Devil, and he’d warned every person since then not to take the deal. In fact, deals with the Devil have been dropping these days, what with the new Quirks and all that. 

He can’t stay any longer on this plane, the miasma calling his demon side back to hell. He’d normally ask the person who summoned him to reconsider, but the boy is unconscious and the demon part of him can’t go back unless he brings the boy with him. Not doing so would kill him, but bringing the boy - the boy, he’s only five or six! - would doom him to a sinful life.

His selfless side tries to break free, but he is a demon at the end of the day, so he scoops up the small boy’s body into his arms and walks back into the fading light. 

It shuts behind him as he crosses the border between the worlds and he sighs as the world around him begins to shift and swirl until all the colours are mixed into a grey background around him. One more life to the darkness. He hopes that the boy had a good reason for this. He better.

He takes one of his claws and digs it into the palm of his hand. The blood wells up and he smears it on a few of the boy’s biggest injuries, the cuts sealing up almost immediately. The boy is at least a little part-demon now, but Mephistopheles shrugs, assuming that the boy knew of the consequences of summoning a demon, meaning he can’t be at fault. The boy must have known, right? It’s written in Daemonics, meaning he can read it, so of course the boy can read it too.

He stills at that, before looking at the boy. The boy is human. Was human.

Ugh, Faustus is going to kill him again.




Izuku wakes up in someone’s arms. The figure seems to have not noticed him yet and he’s too lethargic to do much. He also has a headache from his senses. His eyes are sharper than usual and the increased sight, along with his new sense of smell and hearing, are giving him hell. 

The figure stops at a huge wooden door, painted half black and half white. The white side is covered in scratch marks, while the black side is immaculate. The man uses one hand to carve another gash into the white half of the door and the door swings open immediately after. He hears commotion on the other side of the door, and it only gets louder once the door is open. The figure takes a few steps in and everything goes silent. Izuku uses this opportunity to peek over the figure’s arms. He wriggles a bit and the figure looks down at him, their beady eyes glinting like two pieces of coal.

“Hush, wait.” And Izuku does.

The figure walks up to the staircase, their footsteps echoing in the now silent banquet hall. From Izuku’s peephole, he can see a red man sitting on a huge opulent throne, with horns and claws and wings and fangs.

The figure shoots him a little smile, before ushering him up the stairs. He can feel every pair of eyes on him and he has to resist the urge to curl in onto himself. He gets to the top of the stairs and the man sitting on the throne smiles at him. It’s not a happy smile, or even a sad smile, like the ones he sometimes has, no. It’s a scary smile, a vicious one, like how a predator greets its prey on the field.

“Well, hello there, little boy.” The shadowy figure smirks, their razor-sharp smile glinting in the low lighting. He crosses their hands together, their claws clicking against each other, with the sound being the only constant in the endless chaos surrounding them.

“H-hello.” A six year old Izuku says, looking the shadowy man in the eye. The shadow man scares him, but Mama always said not to be rude to strangers and the man hasn’t done anything bad yet. 

“Why did you summon this...filth, human.” The man says, scoffing at the figure at the bottom of the stairs. It’s worded more as a statement than a question and Izuku tries to find the words to respond.

“I got lost and I found a beach covered in trash. I cleared some of it, I cut myself a few times and I found the box. I drew the thing, and now I’m here.” Izuku glances at his cuts, some of which are slowly stitching together in front of his very eyes. He looks back at the man. “I’m lost.”

The man laughs loudly, the sound echoing through the chamber. Everybody else stays silent. “No, my dear disciple, no, my-” The man stops as he thinks of a word, clicking his claw on his chin. “-child, you’re right where you belong.”

“What do you mean?”

“I will take care of you, I will give you power.” The man says, not phased by the boy’s questions.

“But I’m useless, a useless Deku! I’m weak.” Izuku replies, looking at the floor.

“Ah, ah, ah. Don’t look down anymore, you’re one of us now.” He says, the ‘s’ sound in us being elongated,  “I can give you all you seek, if only you follow me.”

“See, this here, can give you what you desire.” The man says, gesturing to a luminescent orb with one sharp claw. “So how about it?” The man’s eyes narrow to little crescents, his red irises staring at Izuku. Coupled with his almost feral grin and his general appearance, to Izuku, he looks like a demon, like the Devil.

“How would you like to have a Quirk?”

Izuku gasps at that, in excitement or in shock, he’s not quite sure. “Really? You’ll give me a Quirk?”

The man chuckles at that, grabbing onto Izuku’s chin with a clawed hand. He pulls the boy closer to him and whispers in his ear.

“Of course, son. Sinners stick together.”




Izuku is deposited on his doorstep a few hours after he summons Mephistopheles, right as the sun is setting. Well, that ‘few hours’, that’s in human realm time, at least. His stay in Hell (he learns that’s the name of the place after a few days) lasts one year. In this one year, he learns how to use his new power, learns that maybe sinners and demons might be nicer than angels and saints, learns how to use glamour to disguise himself as a person. 

He spends most of his time down in Hell learning about the people there, and their stories of how they fell from grace. Belphegor was condemned for curiosity. Gusion was shot down for defying an oracle with his visions. Orias fell because he interfered with the stars and their visions, telling people how he could decipher them. And as Izuku listens to more and more stories, he comes to realize that maybe angels are the real demons and that maybe he, a sinner and someone fallen. Maybe he can be great.

He no longer thinks of himself as useless. One might say that his superiority complex rivals even Bakugou now, although that’s not really hard. Being raised by demons will do that to you. He enters the house, no longer a six year old in his mind, though he never really was. He walks into the house, his mom nowhere to be seen. He finds a note on the table: a sentence saying she was never coming back. It mentions that she’d had enough of a Quirkless kid and that while she’d pay for the apartment, it didn’t change the fact that she’d hope he’d rot in hell.

Oh, if she knew.

A baby crow from the cages in Hell perches itself on his shoulder. It chirps at him and he chirps back. Living in Hell made him learn how to read, write, understand and speak both Daemonics and Crowlish, so he can understand what the crow’s saying.

“Your mom leave?”

“Yeah, my mom’s gone.” Izuku twitters, before looking back at the empty apartment. “On the plus side, there’s nobody else here, so you guys can live with me now.”

At that, three more crows poke their heads out of his hair. “Really?”

“Yeah, not like anybody’s going to tell you to leave. Just keep clean and don’t leave feathers everywhere.”

They fly into the room, setting up a nest above their kitchen cabinets, while Izuku dumps the contents of his tattered backpack onto the couch. He’ll check on that later. He walks to his mother’s previous room and looks at the door for a while. He uses magic to lock the door shut - permanently. The door fuses with the door frame and Izuku walks back to where the baby crows are crowding. The first one was a dark black, colored like a normal crow, but the other three are a bit different.

One of them is a bloody red, with its feathers catching alight after they fall off, and another is snow white, with its plume freezing any surface it comes into contact with after it’s removed. Mephi (yes, he calls Mephistopheles Mephi) gave him the black, white and red ones, but the last one is from Dad himself. It’s a green color, the color of Izuku’s hair. He’d asked Dad for it to be exposed to his magic, so it would turn into the emerald in front of him. It’d act as his last reminder to his old life once he’d switched to his new identity. 

Speaking of Dad, he’d been busy these past few weeks in Hell, preparing for Izuku to come back to the human realm. The Devil’s really not scary once you get to know him, but that might be because he adopted Izuku as his son and even demons have familial ties.

He adjusts his glamour a bit, removing the color disguise on his hair, leaving only the style of his new longer hair. His horns and claws - of course - are still hidden. He doesn’t need invasive questions. His face smooths over a bit, removing the freckles he was once proud of. His eyes turn crimson and become more slanted and angry. He notes that he’s starting to look like a red-haired Bakugou. He looks in a mirror and makes an agreeable sound when he looks almost nothing like Izuku did.

For sinners are damned, and Izuku is a sinner. Sinners have fallen from grace, not allowed anything, let alone being allowed to be a hero. His Dad wasn’t happy about that, but he’d agreed, as long as he’d stick to his original goal. (His Dad also told him to take his name, and Izuku hadn’t seen a reason to disagree.) Sinners are hunted and killed, and he has a mission.

For Midoriya Izuku is dead now, and in his place, stands a demon and an imposter. 

In his place stands Akatani Mikumo.