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The Tenth Mystery: The Demon Asta

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Most days Yuno doesn’t feel like he goes to the most renown school in Clover City.


It all boils down to the people he studies with, and the thing he’s made to do. Yes the education is first class, and so are the facilities, but with the amount of chaos that goes down on the daily it almost feels like he’s in some twisted amusement park instead of a school.


“Yuno look out!”


That small warning is all he gets before his thoughts are promptly interrupted by the same chaos he’d been alluding to. He doesn’t even utter a groan as something hard collides with the back of his head, sending him stumbling forward over his cleaning supplies.


He hears both laughter and gasps of fear behind him, and when he turns to look he sees exactly what he expected to see. His classmates are all standing in the hallway, which is covered in soap and water in what is supposed to be a method of cleaning, but is only helping to mess it all up even more.


Something clatters beside him and he looks down to see the object that had attacked him just a second ago. A bucket, he wonders how the hell someone managed to accidentally throw a bucket at someone, especially so hard and fast.


If it was indeed an accident. Part of him doubts that it is.


“I’m so sorry Yuno! You see David didn’t want to hand over the bucket and we were fighting over it and-!” Mimosa quickly apologizes, fearful of his wrath.


But Yuno is too tired to be angry, and if it was Mimosa he could let it slide. “Whatever.” He kneels down to pick up the bucket, tossing it back to them without more protest.


How the hell did he get stuck here again?


Right, cuz all the freshmen had to help clean the school. Why? They said it was to build discipline, but Yuno can’t help but he resentful anyways, because there are people they pay for this right?


Yuno rubs the back of his head, over the area the bucket had hit him, and groans inwardly at the bump he can already feel forming back there.


He decides to ignore it and picks up the mop, sweeping the floor with practiced ease as he tunes into the conversation behind him.


“You heard about it right? The rumors?”


“Which one? I hear there’s like seven!”


“No, there’s ten! And they’re all super creepy!”


Yuno rolls his eyes, wondering who in their right mind would believe things like ghosts and demons really exist.


“Oh I’ve only heard seven, what are the other three?”


“Well eight and nine aren’t that special, but the tenth? It’s so tempting I might just go over and do it myself!”


“Well what is it?!”


“I heard that if you go to one of the bathrooms in the oldest building of the school there’s a spirit that grants a wish to anyone who asks!”


“That sounds way too good to be true!”


“Thing is there’s a catch, if you wish for something the spirit takes something from you in return. It sounds scary but image of it was real!”


Yuno decides he’s had enough nonsense after hearing that last part, because that’s ridiculous. Dreams don’t come true, everyone knows that, especially him, because if they could he would’ve wished for his memories back long ago.


He quickly picks up his things and starts making his way to the next hallway over, which ironically enough is the oldest building. No one has bothered to clean this area yet, and Professor Vengeance had explicitly told them to clean every part of this floor, so it had to be done.


He works in silence for a bit, listening to his classmates fool around in the hallways nearby. He wonders how long it will take them to finish, because he could really use a hand, but he’s never been one to ask for help, so he just grits his teeth and keeps going.


Soon enough he’s done with the hallway, and so he moves to the most dreaded part of it all, the bathroom. It’s the oldest building, so part of him hopes no one uses these bathrooms very much.


Yuno enters the bathroom with his supplies, dumping them by the door and looking at the rusty stalls with nothing short of dread. Whatever, the sooner he starts the sooner he finishes. He really should hurry, he notes as he looks out the window, the sun would be setting soon.


He kneels next to his supplies and grabs the mop once more, but stops when he hears the door to one of the stalls close shut. He turns his head, very aware of how it couldn’t have slammed on its own, since the window is closed.


Maybe someone already came in and was cleaning when he arrived? Or someone was using it. Whichever it was he should make sure before he starts cleaning, he doesn’t want anyone tripping over a wet floor.


He walks over to the stall, the very last one. There’s definitely someone inside, because its locked, and the door had been wide open when Yuno came in.


Yuno’s fingers graze the wooden door three times, the sound much too loud in the quiet bathroom.


“Is someone in there?” He asks. No answer.


“I know you’re in there.” He sighs, “Can you please hurry? I need to clean this place.”


More silence. And then the lock clicks, Yuno lowers his hand from the door and watches as it slowly drifts open. But no one comes out, and Yuno begins to feel his patience wear thin.


He opens the door forcefully, showing the empty stall in all its rusty glory. Yuno blinks, wondering if they crawled under the gap between the stalls.


“Back here buddy.”


The sound of a voice right behind him triggers his reflexes, his elbow bending backwards to drive it into the person’s face. He misses, and part of him is glad that he missed until he sees what’s behind him.


There’s a boy behind him, a good four or five inches shorter than him, with spiky grey hair and bright green eyes that are staring up at him. Yuno can only see one of his eyes though, because his hand is phasing right through the other one, obscuring it from view.


They stand here in silence, with Yuno’s hand run straight through the boy’s head, and it’s not until the boy tilts his head sideways that Yuno understands he should be freaked out.


His hand is out of the boy in seconds, his back pressed to the stalls as the boy blinks owlishly at him.


“Woah you ok there dude? You look a little pale.”


Yuno’s eyes narrow, and he takes in every detail of the stranger with careful precision. He’s wearing a tattered uniform that doesn’t belong to their school, there’s a headband in his hair that has a logo with a bull’s head, and there’s a lot of scratches and scars over his arms and face. He’s the perfect image of a troublemaker if Yuno’s ever seen one.


“Who the hell are you?” He asks, calm and collected.


“Who am I? Didn’t you come here looking for me?” The boy shoots a question back, crossing his arms.


“What? No, why would I be looking for you?”


“Well you came into this decrepit bathroom at sunset, knocked on the door to my stall three times and asked if I was there.” As the boy lists off the things he’s done he raises the fingers on his right hand. “You followed the steps to summon me perfectly!”


Then something clicks in Yuno’s head, like the spark that comes out when you high wire a car. He remembers what his classmates had been talking about earlier, about the ghost that lives in the bathroom in the oldest building.


It couldn’t be a coincidence right? Someone was definitely playing a prank on him.


“Oh I get it.” Yuno pushes off the stalls with a sigh, pinching the bridge of his nose, “I don’t know who in my class set you up for this, but you should stop this prank before you get in trouble.”


His words make the boy frown and then he’s at Yuno’s level, floating off the ground so he can match his height.


“You think I’m fake? Just look at me! I’m the real deal!” The boy reaches forward and his hands phase through Yuno’s chest, sending a chill up his spine.


Yuno admits it’s hard to counter that, and he struggles to find any kind of projector that might be around the room, but there’s none.


“Stop that!” Yuno bats him away, shivering, and although the action doesn’t affect him at all the other still stops. “You can’t expect me to believe you’re really a ghost that grants people wishes, that’s ridiculous.”


“It is not!” The boy huffs, getting right in his face again. “I’ll prove it pretty boy!”


Yuno doesn’t like the implications of that sentence.


Before he can voice a complaint however he watches the boy pull out something from behind him, a book of sorts, but the cover is too worn and dirty to make out any sort of title.


“What are you doing?” He’s almost afraid to know the answer.


The boy grins, and Yuno’s head snaps to the bathroom door as it slams shut behind him. The room suddenly darkens, the light of the setting sun no longer casting its orange rays on them.


“I’m Asta by the way,” Yuno looks at the boy as a black figure looms over them both, standing behind his floating body, “They call me the tenth mystery. The Demon.”


The darkness is terrifying, it’s cold and deep, he almost feels like he’s sinking. Asta is looking at him expectantly, but Yuno isn’t looking at him, he’s looking at the demon that’s grinning at him. The creature points, it’s long fingers hovering over his head before it speaks.


Be careful.


The warning is unexpected, but Yuno doesn’t flinch back from it. He stands tall and glares up at the demon before looking back at Asta.


“Alright I get it, you can stop.”


His words seem to surprise Asta, though maybe it’s just the fact that he doesn’t seem scared of the giant demon in the room with them. That’s not exactly true of course, because Yuno can’t even begin to try and wrap his mind around all of this.


Still his act is enough to convince Asta, and the ghost closes his book, calling off the demon as twilight shines on them through the window once more. Yuno relaxes slightly, feeling like he can move again.


“Do you believe me now?” Asta grins.


“Not a chance...” Yuno says, turning around and making his way to the door.


“Hey hey where are you going?! I still need to grant your wish!” Asta calls from behind him.


“I don’t have one, so go back to your stall or whatever.” He has no intention of getting mixed up with demons, no thank you.


“But I can’t leave until I grant your wish! Get back here!”


“No! Leave me alone.” Yuno walks faster, completely forgetting his earlier task.


Asta is suddenly in front of him, and Yuno steps backwards. “I’m serious, I don’t want your wish, I already know your deal!”


“You mean the price? Don’t worry about that! I’d never take anything too precious from you!”


His words make Yuno stop, and he glares, “Me? Why?”


Asta pales, and Yuno wonders if he’s hiding something. Whatever, it’s not like he cares.


“W-Wait! I promise I’ll do anything! No price!”


Yuno actually thinks about it for a moment, because this kid was the real deal and he was promising one wish for free. Maybe...


“Anything?” He asks, unsure.


Asta perks up at his interest. “Anything!”


“Alright, then I do have something I really want...” Yuno gazes out the window for a second. “You see, not too long ago I lost my memories... I think there was an accident or something. I would really like to have them back.”


He looks back at Asta, seeing he’s gotten pale all of the sudden. The ash blond averts his gaze and chuckles.


“Memories huh? Sorry bud but I can’t help you with that!” He says in mock cheer, grinning. It’s fake.


He’s hiding something, Yuno can tell.


“You can’t? Or you don’t want to?”


Asta flinches.


“You can.” Yuno’s eyes narrow.


“No I really can’t! I know I said no price but things like that are uh-! They’re expensive!” Asta waves him off.


Yuno hums, because although Asta is a bad liar he can already tell he’s not going to get anything from him like this. Well two can play at that game.


“Fine, I guess I do have another wish you can grant for me.” He crosses his arms.


The ghost relaxes instantly, reaching for his book, that’s exactly what Yuno was waiting for. He needs to get that.


“Tell me, what is it? I’ll grant it no questions asked!”


Yuno nods, “There’s this boy I like, make him fall in love with me.” His tone is flat.


There’s silence following his words, and Yuno can tell Asta has stopped functioning for a few seconds.


“A-A boy huh...?” Asta chuckles, “Ha ha...”


His hands fall slightly, his grip going slack around his book. Yuno takes his chance then. He reaches for the book and snatches it out of the ghost’s hands, surprised that he can actually hold it.


“W-What the-?! Give that back!” Asta reaches for it.


Yuno keeps it out of reach, evading the ghost’s hands even as he flies full speed at him.


“You’re not getting this back until you grant me my wish.” He states, dodging Asta once more.


“I told you I can’t! Now give that back before something happens!”


“No, not unless you give me your word that you’ll grant my wish.”


Asta grits his teeth in frustration, groaning. “Look I can’t! I don’t grant wishes like that!”


Yuno raised a brow, because it’s an obvious lie. “Fine then.” He flips the book open and begins reading through the pages.


“Hey stop! Don’t do that!”


“I won’t stop, if you won’t grant my wish I’ll find a way to do it myself.”


His hand touches the pages, and Asta gasps as a light begins to emit from it.




Yuno gasps as the book burns him suddenly, and he let’s go of the item as his vision begins to swim. Asta is somewhere in his peripheral vision, but he can’t focus on him as his eyes close against his will.



“Yuno! Hey Yuno! Wake up!”


Yuno closes his eyes tighter as a loud voice interrupts his sleep, curling further into himself when his head thrums uncomfortably. But the voice persists, and Yuno is forced to open his eyes and pay attention.


“What is it?” He asks, but the sound of his voice surprises him.


“Finally! I was so scared you died back there!”


Who...? What? Why would he die?


Yuno blinks a few more times, finally locking eyes with Asta as the other looks down at him. Oh right, ghost, demons, wishes, he’d touched the book and passed out. That must be why Asta is above him, and that’s why he...


Wait, since when was Asta that big?


Yuno bolts up, but he’s shocked when he barely comes off the ground. He looks down at himself and stares as he sees a body that isn’t his own, that isn’t human.


“I’m... a bird?!”


He is! When he moves his arms wings flap instead, when he opens his mouth there’s a beak that speaks for him. He’s a bird!


“Asta, what the hell happened?” His voice is just barely calm, and the squeakiness of it doesn’t help the rising panic.


“It’s because you touched my grimoire! Humans aren’t supposed to touch it! If they do they get cursed!” Asta says, clearly angry and exasperated. “I told you to give it back!”


Yuno deflates, silently berating himself for being an idiot. He’d been so desperate for his memories that he went and got himself cursed, just great.


“You’re taking this a lot better than I thought you would.” Asta reaches down and cups Yuno between his palms, Yuno’s both too shocked and tired to protest.


“Yeah, I suppose I got myself into this.” He answers, shivering and watching as his feathers ruffle.


“Hey hey don’t look so down! I still need to grant your wish remember!” Asta lifts him up, smiling.


“You can turn me back?” He asks, hopeful.


“Yeah!” Asta’s face then turns dark, “But should I? You’re much more obedient like this, cuter too! And you’re right, you deserve it for not listening to me!”


Something inside Yuno snaps, all of the day’s events catching up to him and fueling a rage he’s very unused to feeling. He flies up to Asta’s face at full speed, pecking his forehead over and over until the ghost is begging for mercy.


“Yuno waitwaitwait! I’m sorry! Ack! Stop that it hurts!” Asta swats at him, but Yuno isn’t done.


“Then turn me back.” Yuno huffs, continuing his assault.


“Fine fine! I was only joking! I’m sorry!”


The apology calms him down, and Yuno perks himself on Asta’s shoulder with as much anger as a six inch bird can muster. It must look amusing, because Asta laughs as he grabs his grimoire.


Asta holds his hand out to Yuno, and he hops onto it without another word, his black feathers finally smoothing out against his body.


“I can grant your wish Yuno, but since this is a pretty heavy curse it’s gonna take a little payment.” Asta says, sitting cross legged on the floor.


“What’s the price?”


Asta looks at his grimoire, still smiling, “Your body!”


If Yuno had visible skin, he would pale.


“My... what?” Is he saying what he thinks he’s saying...?


“If I grant you this wish then you’ll become my human assistant! Which means you have to do whatever I say!”


Yuno’s anger almost returns, but he quiets it, Asta’s clearly an idiot, he probably didn’t think that statement sounded wrong at all.


“Fine I guess.”


“Cool! Now then!” Asta sets his grimoire down, cupping Yuno between both his palms once again before he leans down.


“What are you...?”


Yuno’s cut off as Asta’s soft lips press against the top of his head, and he gasps at the warmth that it spreads through him. The feeling is almost familiar, but he doesn’t get the chance to ponder it too much before everything changes.


Next thing he knows he’s on top of Asta, their faces close together with the other’s hands firmly on his waist. His own hands are on each side of Asta’s shoulders, his legs settled between ghost’s


He doesn’t blush, he really doesn’t, the heat on his cheeks is just his imagination.


“Sorry about... that...” Yuno says slowly, unable to find it in him to move.


“I-It’s alright, really.” Asta grins, and although it’s lopsided there’s definitely a blush on his face.


Yuno quietly shifts to push himself off, but then he notices something.


“I can touch you now.” He says, looking down at Asta’s hands that are still on his waist.


Asta seems to realize what he’s doing and quickly scuttles away, floating off the ground and grinning still.


“Yeah! I told you we’re bound now right? That means we can interact normally from now on!”


Normally his ass, what about this was normal?


“I see.” Yuno stands up, dusting himself off and facing the ghost.


“Well in any case, thank you for granting my wish.” Yuno admits, glancing out the window, seeing the sun has finally set.


“Don’t thank me yet! Because...”


Yuno turns back to Asta as the other trails off, eyes widening when the other floats forward and grasp both his hands. The spirit intertwines their fingers, smiling brightly at him though pointed fangs.


“Even if I can’t give you back your memories, I intend to make every other one of your wishes come true.”


Asta says it with such devotion, and the gentleness in his voice brings that warmth back to his face. It’s such a new sensation, yet overwhelmingly familiar. Yuno wonders where Asta’s words come from, why he’d promise something so deep and sincere to a boy he just met.


But still he smiles, swept away by this feeling of belonging he can’t quite place. He wants to revel in it, now and forever.


“Then I’m in your care.”