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The Demon Prodigy

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It would have made a peaceful scene — a soft beam of light shattering into multicolored facets through the glass window, the gentle sound of pens scratching on paper and the clicking of keyboards forming a busy hum throughout the Armed Detective Agency — that is, unless, of course, you were to ignore the angry screeching coming from a certain idealist.




Atsushi sighed. “Sorry, Kunikida-san. I won’t turn in my reports late next time.” But honestly, it wasn’t like he could ignore the work Dazai-san gave him either! His mentor saved his life, he at least owed him that!


Kunikida huffed, and as if he had read his mind, responded, “At least you have some semblance of responsibility. Speaking of, don’t worry about the bandage waster’s work. I’ll get him to do it.”


Atsushi sweatdropped. Good luck with that. Suddenly, frantic knocking rang out from the front door. He blinked. Although a new case was hardly unusual, most people simply rang the doorbell.


Kunikida strode over to the door. Clearing his throat, he opened the door with a jerk. Before him stood a nervous looking middle aged man, clutching an envelope in his hands. His eyes lit up at the sight of the blonde, and using his free hand, he grabbed Kunikida’s forearm, eyes darting around the room all the while.


“Thank God you’re here! Please help, I have money, he- he’ll kill me!” The man spluttered out. He ran into the room, and closed the door behind him. The envelope was shoved into Kunikida’s hands. “Please, I- I know what I did wrong but I have a family! I have kids! He’ll kill them all!”


Kunikida’s brows furrowed. “Calm down. Who’s trying to kill you, and what’s in this envelope?”


“The-” His eyes glanced around the room. In a whisper, he finished, “The Demon Prodigy.”


Kunikida’s face blanched, and he guided the client to sit down at one of their tables. Atsushi felt a small hand grip onto his sleeve. Kyouka’s eyes were wide.


“Are you sure? We can ensure your protection, but why would he be after you?”


The man swallowed. “You promise you’ll protect me?”


“To the best of our ability.” Kunikida responded.


“Well I- I- I… I stole from a group of gang members a couple days back. I didn’t know they were his, I swear! And a few hours ago I got that in the mail.”


Kunikida carefully lifted out the message. He stared blankly at it for a few seconds, before standing up and turning to the rest of his coworkers. “Call a meeting, now! Brat,” he spoke to Atsushi, “call the lazy bastard and get him to come. We’ll start as soon as Ranpo gets back with the President. Yosano-sensei, can you lead him to your, er, office? He’ll be safe there.”


“Whatever you say, Kunikida.”


“Kunikida-san? What’s going on?” Tanizaki asked.


He took a deep breath. “It seems as though the mafia has broken their truce.”


Tanizaki gasped. Atsushi turned to Kyouka. “Are you alright?”


She gave a small nod. “I will be.”


“Oh, that’s good.” Demon Prodigy? I wonder who could possibly spook Kyouka like that...



“Ranpo, Shachou. I’m glad you’re here.” The door squeaked closed behind them. Chairs scraped against the floor as all the detectives respectfully stood up at the sight of their president.


“What was the purpose of this meeting, Kunikida?” Fukuzawa asked, his steely blue gaze travelling around the room.


Ranpo took out his glasses. “Wait, wait, let me guess! Hm…” His eyes snapped open, revealing sharp emerald irises. After a moment, he let out a snort. He collapsed into his chair, and banged his fist against the table in silent laughter before looking up and pointing to Kunikida, his glasses now sitting haphazardly on his face


“Er, Ranpo-san?”


“You! I was going to get mad at you for wasting my time, but this is actually funny!”


Kunikida blinked. “Huh?”


Ranpo only smirked and wiped down his lenses. “Well, once Dazai gets here, we can start.” He rubbed his hands together and manifested a bowl of popcorn out of seemingly nowhere. The president, unfazed by his antics, simply sat down and poured a cup of tea for each detective.


As if he had been summoned, Dazai chose that moment to open the door, with all the extravagant gracefulness of a cat. Two small leaves rested on top of his hair, as if he had been sitting under a tree for some time. “I heard there was an important meeting, Atsushi-kun?”

“Ah, actually, Kunikida-san called you here…”


“Aw, someone missed me~”


“No, you- You know what, nevermind.” Kunikida pushed up his glasses, its lenses briefly flashing. “We have received evidence that the Port Mafia may have broken their truce.”


Fukuzawa’s face hardened, while Ranpo only threw a handful of popcorn into his mouth. Dazai sat down, an intrigued expression on his face.


Kunikida took a deep breath. “Our client claims he received a threat from the Port Mafia. It reads, ‘I know you intercepted and stole a shipment of our supplies a few weeks ago. Return them immediately, with an extra sum of ¥100,000,000 if you want to keep your family alive. And don’t you dare ask the Armed Detective Agency about this, or we’ll slit their throats as well as yours.’ This is a clear threat from the mafia, which is a violation of our agreement. The question now is whether this note is legitimate.”


“Uh, Kunikida-san?” Atsushi raised his hand cautiously. “Where does the Demon Prodigy play into this?”


Fukuzawa raised his eyebrows, and lifted the tea to his mouth…


“The note was signed. It reads, ‘from the Demon Prodigy of the Port Mafia’.”


… and promptly spit it out.


The sound of Dazai’s sigh was audible through Ranpo’s wheezing.


Kunikida blinked, and the feeling settling in his chest only deepened, reminiscent of when the bastard somehow told everyone but him that he used to work for the mafia. The feeling that he was missing a piece of the puzzle, made of pure confusion with a hint of despair. He desperately looked around the room for help. His eyes met Yosano’s, but she just shrugged and lifted her cup to her mouth. Fuck. He was going to have to do this alone.


“Er… Well, uh, Kyouka-chan? Do you know of this Demon Prodigy?” Kunikida asked, determined to ignore the now coughing President and the two detectives for as long as possible.


She nodded, and her piercing blue eyes locked onto his. “I’ve heard of him. He was the youngest underboss and executive in Port Mafia history. He was charming, clever, cruel, and struck fear in his subordinates, the perfect model that we all strove to be. Akutagawa-san and Chuuya-san were both recruited by him. Some say that he was the one that put the current boss on the throne. But four years ago, he vanished. Most think he died, but I heard a few senior members say he was famed for being able to have a picnic in open gunfire and come out unscathed. There are rumors that he just… left. His ghost still haunts the halls, and no one dares say his name. He’s a mafia legend.”


“H- His ghost… is that true?”


Kyouka nodded towards Atsushi, dead serious.


Dazai groaned, and mumbled something indistinguishable under his breath.


A shiver ran down Kunikida’s spine. If he was so terrifying, why had Ranpo laughed? He reluctantly turned towards his partner.




“Hm?” He propped his chin up with his fist. Ranpo and Fukuzawa had finally collected themselves behind him.


“You were in the mafia before Kyouka-chan, right?”




“So, what do you know about the Demon Prodigy?”


Dazai paused, looking out the window. A few seconds passed in silence. “Same as Kyouka-chan, really. I doubt he truly died. He still lives in the shadows of Yokohama, kept there by a promise he made to a… friend. He only appears when situations are dire, but he won’t make a full return anytime soon, if I can help it. I can promise that.”


Kunikida blinked. His partner rarely talked about his time in the mafia, usually just dodging the question or providing as little information possible. And the information he gave was even more confusing than usual. A friend? Shadows of Yokohama? What is he on about?


Atsushi’s voice cut through the silence. “Dazai-san, did you... know the Demon Prodigy?”


“You could say that.”


“...Were you that friend?”


Dazai snorted, turning back to the window. “No, I wanted to kill the Demon Prodigy for the longest time. I still do, sometimes. His friend was a much better person than I am, or will ever be. But I can try.” An unreadable expression crossed his face for a few precious seconds, before he turned back to Kunikida with his signature cheeky smile. “Well, the point is, that’s a fake note. For all intents and purposes, you can assume the Demon Prodigy is dead.”


Something about the way he spoke nagged at Kunikida, but he couldn’t quite place it. His brows furrowed with confusion. “How can you be sure?”


Dazai let out a bitter laugh. “You’ll just have to trust me, partner.”