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Operation Gemini Days

Summary:

As the Nocturnal Detective Agency are closing in on their battle against Amaterasu Corporations, two detectives find out about each other’s special days and ropes the Master Detectives and their informant to help plan for the other’s birthdays. Without either of the two knowing their plans. So the Master Detectives and their informant must pull off two birthday parties for their teammates without either of them figuring out what they’re play at, and give them the best birthdays they ever had for a long time.

A Yakou and Yuma Birthday Fic

SPOILERS FOR UP TO RAIN CODE CHAPTER 4

Chapter 1: Discoveries

Notes:

(See the end of the chapter for notes.)

Chapter Text

The mission to solve Kanai Ward’s Ultimate Secret has never been more tense. Progress has been made now that they have an actual goal outside of solving the hundreds of mysteries plaguing the city. Which is to find a secret lab and uncover Amaterasu’s research project: the creation of immortal monsters known as Homunculi. No longer having to wander the streets aimlessly, they have a mission to complete now. 

But even with the goal in mind now, searching for the secret lab has been taking longer than they thought. Even with the new help from the unofficial informant of Kanai Ward, it felt as if they were searching for a needle in a haystack. ‘You would think having a goal now would make solving the mystery much easier?’ Is what everyone thought. No one knows about the Secret Lab, not even in the underbelly (sewers) of Kanai Ward. Not even people who may have worked for Amaterasu beforehand. The trainee has mentioned having encountered someone who ended up ‘disappearing’ due to finding out information about Amaterasu, and it would seem it may have increased just as they have finally found an important clue. A bit too much of a coincidence…

Regardless, no one was going to fall to such obstacles, not when they are so close. They need to end this nightmare. Tensions had never been higher between the Peacekeepers and the detectives. They can’t risk squandering any more of their time solving the mystery.

Until one day, Yakou called in for a meeting with the Master Detectives at the Agency. Everyone has gathered in the main base, with the Chief relaxing in his chair as usual. Fubuki and Desuhiko sit on the white couch together, the former sitting properly like in a chair and the latter leaning to the side. Halara rests in a chair they pulled out from the Agency’s storage area, or corner more like it. And Vivia in his usual place, somehow fitting into the fireplace.

Yakou claps his hands to get everyone’s attention. “Alright, now that everyone’s here, let’s get this meeting started.”

Which was strange to say because one of their own was still not here…

“Hang on, where’s Yuma? Shouldn’t he be here too?” Desuhiko pops the question.

“Don’t worry, he’s still out working with Kurumi on their patrol. He shouldn’t be in this meeting anyway.”

Desuhiko tense up. “Huh, why is that?” 

“Is the topic of this meeting not something you want for him to hear?” Halara queried.

Fubuki suddenly gasps and springs out of her seat. “You’re not planning to fire him, aren’t you?! Please reconsider, Chief! He has been nothing but kind to all of us! It is not his fault that he is a curse in our Agency!”

“Hey, hey! Relax, Fubuki! I’m not firing him-” Yakou springs out of his chair and points at the detectives. “Wait, who said he was a curse here?!”

Fubuki’s eyes widened at what she said, and turned away, refusing to speak. No matter how much Desuhiko tries to probe her on who was talking bad about his man. Halara and Yakou look over anyone for any signs that someone could have mocked their youngest member.

Yakou eventually just sighs and collapses back into the chair. “Never mind; I’ll figure that out later. But don’t worry, this meeting is actually a good thing for Yuma.

“A while ago, I was searching through the documents we had to make sure if the CEO guy hadn’t created any misinformation to lead us astray. Halara and Desuhiko, of course, helped me out as well.” The two said detectives nodding with prideful smiles. “And when I was looking through Yuma’s profile, I caught an interesting bit of information on it.”

Yakou pulls out the said document and holds it in his hand. “I didn’t really look at it a lot since I got the profile, and I wanted to know if this information was right. So I decided to check with Yuma and see if I can get a reaction out of him. And this was what happened…”

Kurumi has just left the Agency after saying her goodbyes to both the Chief and Yuma. The trainee collapsed onto the couch, putting his legs up on the cushion and trying to even shift the pillows to be under his feet. The Chief takes pity and goes to help.

“Long walk today?”

Yuma releases a heavy sigh, throwing his head back. “Yeah. We searched through all the streets in Kanai Ward. Kamasaki. Ginma. Even the refugee spot where those from Marunomon are staying. Kurumi did try to get us to go to Dohya District, but I managed to talk her out of it thankfully.”

”Nice idea. That district is still riled up after what happened with the Resistance.” Yakou chuckles as he helps get the boots off Yuma’s feet. “I’m glad she’s keeping you out of trouble, but I did not expect she would be just as reckless as you are. Though, maybe she can help you learn to get you out of trouble yourself.”

Yuma rolls his eyes, but he doesn’t deny it either. He just settles and stretches his legs out across the couch, looking about ready to crash. 

“Before you get comfy there, I need to ask you something quickly first.” Yakou takes out a paper document from his desk and holds it close to him. “I want to check if the information from your profile is accurate and not messed up by the CEO. I know you looked through it while cleaning my desk that one time.” Yuma blushed and turned away, much to Yakou’s amusement. “Think you can help me out?”

“Sure, let me just-“ Yuma begins to get off the couch, but Yakou holds a hand up stopping him.

”Ah, ah. You don’t need to get up. I’ll just read them out to you.”

”O-Okay…” Yuma looked confused, but he didn't go against his Chief’s order. 

Yakou starts listing out the information from the document. His name. His age. His blood type. His weight. His height (Yakou couldn’t suppress his snicker when he read that, much to Yuma’s annoyance). 

Until he reaches a certain set of numbers he is prepared to ask. “Oh, there seems to be a date, but it doesn’t say what for. Does the date May 22nd mean anything to you?” 

Yakou watches carefully for Yuma’s reaction when he asks the question. The trainee’s eyes widen and he goes silent. He can see his brain wracking for information whenever he’s asked such questions. But he didn't answer until what felt like a few minutes passed.

“I don’t think so.” Yuma shook his head. “It…feels like it should be important, but I can’t recall. Sorry.”

Yakou keeps his face neutral and just shrugs in response. “It’s fine, I don’t know either myself. Maybe you’ll remember when your memories come back.”

“Okay, but I don’t remember seeing it when I looked at my profile.” Yuma shuffled and he started to get off the couch. ”Can I see for myself? Maybe that can jog my memories?”

”No!” Yakou says a little too loudly that Yuma flinches. “I mean, no. There’s not much on here anyway.” He puts the document back in the drawer of his desk and shuts it, subtly making sure it’s locked. “For all we know, the date might just be your anticipated graduation date for next year.”

”Uh, alright…” Yuma’s face falls and he looks down to the floor. 

Yakou hummed under his breath. He gets up from his seat and goes behind the couch to ruffle Yuma’s hair. “Hey, cheer up kiddo. I’m sure it’ll all come back to you soon. Just gotta be patient.”

”Yeah, I hope so…” Yuma sighed.

”Well, I’ll let you go back to resting. Just take it easy and I’ll get dinner started.” Yakou heads back to the kitchen, ready to get his task started. 

While satisfied he got his own task done…

“…and that was his reaction.” Yakou finishes the story.

“But what is so special about the 22nd of May, Chief?” Fubuki asked.

Yakou scratched his head. “Well, according to Yuma’s profile, May 22nd is apparently his birthday.”

All of the detectives’ eyes widened at the information. Especially when the date is…

“Wait, that’s less than a week away!” Desuhiko exclaimed, jumping out of his seat. 

“Oh my, we almost let time pass for Yuma’s special day.” Fubuki gasped with her hand daintily up to her mouth. “I’m glad you caught it, Chief. I did not know you can best time as well as I can.”

“But then why go through all the trouble confirming it when you knew Yuma has amnesia? What is your end goal with this?” Halara narrowed their eyes in curiosity and suspicion. 

Yakou glanced away with a sheepish smile. “Well…”

“You wish to make a celebration for Yuma’s day of birth, don't you?” Vivia speaks up with his deduction. “The day draws close to end his current age and make way for the next period of his life. So you desire to celebrate the occasion?”

Yakou grins sheepishly and rubs the back of his head. “Yeah, I thought we would do something nice for the kid. Since I imagine he probably doesn’t remember any of his previous birthdays with his amnesia and all.”

Fubuki clasped her hands together. “A party sounds like a wonderful idea, Chief. We could hire some caterers to get the best sweets, rent a ballroom to hold the party and-”

”Whoa, whoa, it’s not going to be like one of the parties you’ve been to, Fubuki. We don’t even have the budget for it.” Yakou mumbled under his breath. “I was thinking of something smaller and just hanging out together on the sub. I’ll even allow us time off for that day if we want to.”

”Parties are too loud anyway…” Vivia groaned.

“Now hold on a second.”

Everyone speaking shuts up. They turned to Halara who was glaring at everyone with an annoyed look.

”You should listen to all of our opinions before you start jumping into planning.” Halara scolded. “As for my answer, I do not agree that we should do it. Or rather, I will not participate with you guys. We have too much on our hands to engage in such tomfoolery.” 

Desuhiko rubs the back of his neck, looking conflicted. “Yeah, I mean, I want to celebrate my man’s birthday just as much as the rest of you, but shouldn’t we be focusing on finding the secret lab first?”

”Indeed. I will not waste anymore time on another’s birthday when we are running out of said time. This meeting itself was nothing but a waste of my time.” Halara gets off from their seat and starts to make their way out the door.

“Wait, Halara!” Yakou springs out of his chair, nearly knocking it over. The movement itself was thankfully enough to stop Halara in their tracks.

“I know, I know, I’m sorry. I know it’s not the ideal time. It’s just…” Yakou sighs and runs one of his hands over his face. “We’re getting close to Kanai Ward’s Ultimate Secret, right? And we know that it’s going to have to do with Amaterasu Corporations, which means...we will have to face them head on soon.”

Yakou’s fists turn shaky, taking in a shuddering breath. ”But you guys have witnessed it yourself. The detectives that all died before even stepping into this city. People who used to work for Amaterasu are disappearing left and right. Yomi nearly killed us with that missile, which we’re lucky to have even survived at all. Once we go head-to-head with Amaterasu, I don’t think we’re all going to make it out together.” 

”I agree with the Chief.” Vivia speaks up from the fireplace. “We have tangled with Death many times before… She has even claimed many before we even stepped foot into this cage of rain. And soon...we will have to dance on the line of life and death once more…”

“But I will make sure we will all make it out of that line.” Fubuki pops up, clutching her necklace. “I can merely rewind time and no one will fall onto death on my watch.”

“And I don’t go down so easily.” Halara smirks.

”But what if that’s not enough?!” Yakou snaps, a little louder than intended. “I’m not doubting any of your abilities, but there is still a limit to what you can accomplish. And even then, our encounters with death could be inevitable. I just…” Yakou takes off his glasses and looks it over, seemingly staring at his reflection. “I just want us to at least have one last good memory together before we go to battle and possibly...”

The detectives all turn towards each other, eyes filled with conflicting emotions. They are no strangers to danger themselves. Just before they entered the city they were struck with tragedies and losses before their very eyes. But as the WDO would say: emotions must be discarded to reach a perfect solution. They could not focus on their failures and losses, and only focus on the mission at hand. 

Yet…after the submarine explosion, believing they almost lost each other like their comrades… Those feelings had never gone away since then, no matter how much they tried to push it down.

“…So what’s the plan then?” 

Yakou perks up, eyes sparkling, as Halara walks back to their seat. 

“I will demand some form of payment for my service here and the time utilized for this party. So tell me the plan you have so far. Surely with the time limit we have, you must have come up with some ideas to celebrate Yuma’s birthday, right?”

The smile has now taken Yakou’s face. He jumps from the chair, rubbing his hands with excitement. “Alright, here’s what I got so far…”

~*~*~*~*~*~

The four detectives head back into the neon pink city streets, still buzzing on the plans being made for their youngest member. They only burst once they made it back to the hotel and secluded themselves in the usually-empty restaurant. Desuhiko, Fubuki, and Halara all sit together at one table in the corner, while Vivia huddles under the table where he would be sitting, obscured by the table cloth.

“Not gonna lie, I am excited to celebrate my man’s birthday. It’s gonna be a blast!” Desuhiko pumps his arms into the air. 

“This is going to be such a fun celebration.” Fubuki clapped.

Vivia groaned from under the table. “Chief said it will only be a get-together.”

Fubuki chuckled. “But we will be together, Vivia. Don’t be silly.”

”We will need to be extra cautious around Yuma while we are planning for his birthday.” Halara speaks up. “When we are out, make sure no one lets slip of anything going on behind his back.”

Desuhiko points to himself with a thumbs up. “What do you take me for? I’m a detective! I know a thing or two about keeping secrets.”

”I’d be surprised if you can.” Halara smirked before turning serious again. ”But regardless of our new mission, this does not mean we can forget our current mission as well. So don’t use it as an excuse if you start slacking off.”  

“That…sounds like too much work…” Vivia sighed. 

“Well that’s the life of an adult.” Halara rolled their eyes. “So you have to deal with it.” 

Vivia sighed. “I wanna die someday…”

“We’ll be fine, Halara.” Desuhiko leaned back on his chair. “We have dealt worse than this. I’m sure we can handle a little birthday plan-“

Halara shushes Desuhiko before he could finish his comment. As he’s about to open his mouth in protest, they subtly point over his shoulder which he follows. With Fubuki and Vivia—after they kick him to peek out—following along. 

And froze.

At the doorway stood Yuma and Kurumi, deep in conversation about something. Thankfully, they looked to have just come in as the door swung close to shut out the dark streets and neon lights.

“We should refrain from continuing our conversation for now. No talking about our plans, got it?” Halara eyes the three detectives firmly with each word.

”Roger that.” Fubuki salutes. 

“Obviously.” Desuhiko hissed.

Vivia just sighs and drops the table cloth back down.

Their stares seem to linger too long to be unfelt by the two. Kurumi takes notice of them first, then pokes Yuma’s shoulder and subtly points in their direction. Yuma turns and lights up, and starts heading over to them. The detectives all subtly look at each other, silently communicating—begging—to not let slip of their plans.

“Hey guys.” Yuma greets once he reaches them. 

“Good evening, everyone.” Kurumi bows in greeting.

“Good evening to you two as well.” Fubuki bows back.

“Hey, not to sound ungrateful for being here,” Desuhiko jumps in, “but what are you doing here and not at the Agency?” 

”Oh, we were hoping to find one of you guys to talk about something, but I didn’t think that we would find all four of you together.” Yuma says, grabbing onto the chair where Vivia would be sitting. 

“Which is great, so now we don’t have to do a wild goose chase and risk the Chief finding out.” Kurumi beams and clasps her hands.

“What do you mean not to risk the Chief finding out?” Halara queried with a brow raised. “Did you tangle yourself in another case again?” 

Yuma’s face heats up and waves his hands. “I promise you, it’s not that!”

Fubuki gasped and springs out of her chair. “Wait a minute, are you planning to fire the Chief?” 

Everyone blinks at the airheaded detective’s outburst. Desuhiko is not even suppressing the urge to facepalm this time. “Princess, he doesn’t even have the power to do that.”

“Please just tell us before this drags out any further.” Halara pinched the bridge of their nose.

Yuma straightened up. “Right, so what happened was this morning…”

Yuma dumps the overfilled ashtray into the trash bag. Some of the smoke kicks up and nearly gets a sneeze out of him. Shinigami doesn’t help breezing through the smoke, spreading them even further in the air.

‘Please watch where you’re going, Shinigami.’ Yuma wheezes out, backing away from the smoke.

Shinigami ignores him and just floats above his head. “Ugh, this is so boring! How much longer are you gonna do Fuzz Head’s chores?”

“I’m almost done. Just let me organize the Chief’s papers first.” Yuma starts shuffling the documents on the desk and tries to get them in order. 

Shinigami floats down while upside-down, arms behind her back. “Aw, hoping to kiss up to Fuzz Head to make up for the terror attack?”

Yuma flinched, which got a cackle out of the ghost. ‘I already apologized so many times already, and I know I screwed up back then! When are you ever gonna stop bringing that up?’

”Until it’s permanently tattooed on your brain, Master.” Shinigami points her ghostly finger to his forehead. “Gotta always remember the screw ups that you made! That’s a life lesson sent from your death god. Kyahaha~!”

‘I’m pretty sure humans have said the same thing themselves-’ Yuma pauses when he notices a bright orange note fall to the floor. He goes to pick it up and his eyes are drawn to the crude letters in black markings.

REMINDER: GET THE SPECIAL MEAT BUN ON THE 21st!

“Ooh, Master! You’re snooping on Fuzz-Head’s notes? I knew my training would start to pay off~!” Shinigami cooed over Yuma’s face. “Even if this is not what I imagine you would be snooping.”

‘Hey, I didn’t mean to! It landed faced up!’

“Still snooping!” Shinigami grins widely. 

Yuma sighs and gets up from the floor. ‘Say, do you remember where the Chief had his calendar? I know I saw it somewhere before.’

”Nope.” Shinigami turns away. “You’re the detective. Figure it out yourself.” 

He rolls his eyes and starts looking throughout the Chief’s living quarter. Thankfully, it wasn’t too hard since the calendar was on the wall just covered in more documents. He should really talk with the Chief about finding another place to put these papers. 

Yuma pushed away a bit of the paper for a closer look. And as he suspected, there was a crudely drawn party hat on one of the calendar dates: May 21st.

Which is just a few days from now…

‘No way. The Chief’s birthday is coming up! Why didn’t he tell us about it?’

“Probably because it wasn’t any of your business.” Shinigami floated around, leaning back on her arms.

‘What happened to praising me for snooping like a detective?’ Yuma rolled his eyes. 

Shinigami gives no comment this time. 

Yuma drops the papers back to shield the calendar. He goes back to sorting the documents back in order. Making sure the sticky note is still on where it was last time. He just hoped he put it on the right document. 

“So now that you satisfy that curiosity, what do you plan to do with the information? I don’t really see what you can do about it.”

Yuma taps his chin. ’I know I’m not supposed to know about it, but maybe I could plan something nice for the Chief for his birthday?’

”Why waste your time on that when you should be looking for the Secret Lab? We’re so close to the Ultimate Secret, I can almost taste it.” Shinigami drooled in excitement. 

‘We can do both.’ He leaves the Chief’s quarter and goes to the main room. ‘I’ll just get him a gift and that’s it. Or maybe the others and I can all get him a gift together. Maybe I’ll ask what they think if I meet one of them today.’

Shinigami sighed heavily. “I don’t know why you care so much about this, Master. Fuzz-Head doesn’t need any of this stuff.”

”Maybe… But…I like to do something nice for the Chief for once.” Yuma grabbed his rain gear and put them on. “Let’s just go meet with Kurumi for now and think about it later.”

He adjusts the hat and heads out of the sub with his mission done for the morning.

And hopefully the information he has learned will do good for everyone this time…

“…and that’s how I found out.” Yuma concludes to the Master Detectives. Careful to leave out his interactions with Shinigami, of course.

The Master Detectives all stare wide-eyed at Yuma. Not entirely for the shock of how close their Chief’s birthday is as well, but that it’s literally next week as well. A day before Yuma’s own birthday. 

This was…not good.

Kurumi speaks up to continue the conversation. “And after he told me about the Chief’s birthday, I suggested to him why don’t we throw a little party for him as well? Since this would be the first and possibly only time you guys can celebrate together?”

”As much as I like the idea, I’m still not entirely sure about that, to be honest.” Yuma rubbed the back of his head with an uncertain look. “We have like other missions we have to take care of, and I don’t want to make all of you waste too much of your time.”

“Glad someone takes that matter into consideration.” Halara scoffs, pushing their glasses up.

”A party sounds like a splendid idea!” Fubuki cheered and clapped her hands. “He should have a Happy Birthday like everyone else.”

”See, you get it, Fubuki!” Kurumi gestures to her. 

“I’m not sure honestly.” Desuhiko rubs the back of his head with a conflicted expression. “Like Yuma said, we have a lot on our shoulders right now. Like trying to find the secret lab. And, you know, any other stuff we might have on our plates.” He subtly looks over at the Master Detectives in emphasis.

“I think a celebration is in order for the Chief.” Vivia piped up from under the cloth. “We have rocked the boat many times…even sunk it one time… We owe him many gratitudes for the peace and quiet he provided us nonetheless… So why not repay him now?”

Desuhiko leans down and moves the cloth to meet Vivia. “Come on, we don’t cause that much trouble to the Chief!”

”You nearly got the Agency bankrupt on your first mission here.” Halara glared down at the yellow detective.

Desuhiko comes back up to the table pouting.

”Though it is expected that we would have to provoke the Peacekeepers sooner or later to accomplish our mission. No matter how much the Chief tried to hold us back.” Halara pushes their glasses up and glances to the side. “But I will admit we may have not heeded his words more seriously enough times.”

“Yeah, he did look about to have a heart attack everytime we told him we got caught up with the Peacekeepers.” Desuhiko rubbed the back of his head sheepishly. 

”Oh my, I did not realize we were making his heart attack him because of our adventures. We should find a way to calm his heart!” Fubuki says with a determined look. 

“Not what I meant, but yeah. You know what, let’s try to give him a good Birthday as well.” Desuhiko jumps when something hits his legs. “Hey, what’d I say?” 

Yuma’s smile grows, ignoring the strange behaviors. “If it’s something you all agree to, maybe we can plan something for the Chief after all.”

”It is possible as long as we don’t plan so big.” Halara pushes their glasses up. “The best course of action we can do is give him gifts and do an activity together on that day.”

Kurumi nods. “That’s a good compromise and plan for the Chief. I’m sure we can make a good birthday with your planning, Halara.”

“With my logic, anything is possible.” Halara smiles. “I suggest we plan more here to avoid suspicions with the Chief. Kurumi, would you mind informing the Chief that Yuma will be coming back later? We’ll also inform you of our plans later as well.”

“Alright. I’ll just go tell the Chief you’re all eating together for tonight. I’ll be sure not to let slip what you guys are planning.” Kurumi starts getting up and putting the extra chair back. “I’ll see you guys soon.” 

The Detectives all wave back to her as she heads out back into the dark rain. Yuma goes and sits down in the unoccupied chair, careful not to let his legs hit the ghost detective underneath. Halara claps to get the group’s attention, taking charge once more. 

“Let’s try to think of how we can plan the celebration before Yuma has to return to the Chief.” Halara turns to Yuma. “But first, if we’re going to plan here, you need to order something. You are not leaving this restaurant until you eat a full meal like the rest of us.” They order, practically shoving the menu into the trainee’s hand.

With a nod (and some sweat drops), Yuma opens the menu and starts looking for something to order (possibly something cheap). As Desuhiko tries to convince Yuma to order his favorite from their last get-together, a single thought remains in all four detectives’ minds since they learned of the Chief’s birthday. 

They really got their work cut out here.

~*~*~*~*~*~

When the streets outside turn pitch dark, with only the neon lights to illuminate the city streets, Yuma decides to head out and return to the Agency before the Chief gets worried. After some goodbyes were said and any leftovers were stashed in a box for later, Yuma headed out of the restaurant. Once he was out of the hotel, the door closing with a reverberating thud against the silence, the detectives all released heavy sighs.

Desuhiko throws his head back against the chair. “Back-to-back birthdays. I did not think it was possible.”

“It is a possibility in the world, but it is rare to know two people whose birthdays are right next to each other.” Halara speaks, somehow calm as ever. 

Vivia shifts under the table, getting everyone’s attention. “So, we have two incoming days we must celebrate, yet they don't know the other’s plans. But we have the strings in our hands to decide the outcome for the two stars.”

”Yeah, no thanks to you.” Desuhiko pulled up the table cloth to glare at the lazy detective. “Why did you encourage us to do Kurumi’s plan? Yuma was fine just getting gifts for the Chief.”

“You agreed to the plan too, didn’t you?” Halara asked.

“Well, yeah. But because I was being emotionally manipulated by you two.” Gesturing to both Halara and Vivia.

”We did not string you to the conclusion. We just merely spoke the truth.” Vivia calmly argues.

Desuhiko groans and leans on the table, running one hand over his face. “Well, now we gotta worry about planning both of their birthdays without getting caught. How are we gonna get away with this?”

”It should not be that hard.” Halara takes out the lollipop they just put in their mouth. “We just need to time things carefully to make sure the plan goes without a hitch. They don’t want a lot, for each other or themselves, so it should not be this hard.”

”Yes.” Vivia agrees, “There is no need to rile the ocean. We can only ride the waves out as long as we stay on course, and only then we can reach our destination.” 

Desuhiko sighed. “Not making any sense as usual, Vivia, but I get where you two are coming from. Let’s just try to think of a plan on how we do this both ways, and quickly.”

“Think of a plan for what?”

Desuhiko jolts and turns to Kurumi standing behind him. “Ah, Kurumi. Don’t sneak up on me like that!”

”Sorry, I didn’t mean to.” Kurumi blushed.

“What are you doing back here, Kurumi?” Halara queried. “I believe this is not what you meant by ‘seeing us soon.’”

Kurumi fiddles with her jacket strings. “Well, I noticed you guys seemed to be off before Yuma and I met with you. You looked like you were having a secret meeting before we came up.”

”Nice keen eye, Kurumi.” Halara smiles.

”Thank you, Halara!” Kurumi grins before turning a bit serious. “So I want to know what you guys are planning? And I’m not going to leave until one of you spills.”

Halara’s face sours a bit at the stubbornness of the girl, but their brain starts to turn. Desuhiko leans a bit and helps them nudge their thinking, whispering, “I think we can trust her. She won’t want to ruin Yuma’s day, and she might be helping us with the Chief’s too.”

They nod subtly and turn back to the high school senior. “Very well. We will tell you what is going on.”

Kurumi lights up in victory. “Really? What is it?”

“The Chief and Yuma share the same birthdays!” Fubuki jumped and clapped in joy.

Halara sighs and drops their head to one of their hands. “No, the Chief and Yuma’s birthdays are right next to each other. You already know when the Chief’s is, but Yuma’s is the next day, the 22nd.”

“Really?” Kurumi gasped, her eyes lighting up. “But wait, does that mean you’re planning to surprise Yuma as well? Have you guys gotten started planning yet?”

Vivia looks up to meet Kurumi’s sparkling eyes. “We have only discovered Yuma’s birthdate this evening… The future has only started to form in our hands…” 

“Plus, we agreed to do a small get-together for both their birthdays.” Halara adds. “So we won’t be getting too much for either of them.”

Fubuki clasped her hands with sparkling eyes and turned to Kurumi. “Oh, we could use your help, Kurumi. Being Kanai Ward’s only informant and our friend, after all.” 

“She was already gonna help us with the Chief’s birthday, princess.” Desuhiko corrected. “But it would be nice to have more help with Yuma’s birthday as well, Kurumi.”

“Of course I’m going to help plan Yuma’s birthday! I owe him so much for all he’s done to me and the city!” Kurumi thinks for a second and hums. “I can probably help by telling you all the good spots to get the decorations, foods, and gifts you can get. And keep Yuma distracted while you get everything needed.”

“That makes our tasks much easier…” Vivia says with a smile in his voice.

”Great, so with Kurumi’s help, we can give them both the best birthdays they ever had! Especially for my man!” Desuhiko cheers, pumping his fist up. 

“Yes! Operation Gemini Days is a go~!” Fubuki jumped and clapped her hands with a bright smile.

The Master Detectives turns to Fubuki, eyes wide. “Princess, you know what a Gemini is?”

Fubuki tilts her head cutely. ”Yes, it is the twin stars of the Zodiac, and Yuma and the Chief both fall under those stars, correct?” 

”Er, I mean their birth dates technically fall under the Gemini period, but yeah. How do you know that?” Desuhiko scratched his head.

”Well, ever since my parents bought me a star, I wanted to know more about them. So I studied all I could about the stars, and now I am the Master of Astrology!”

“Uh, I think you meant astronomy, princess.” Desuhiko sweat-dropped.

“Huh? Astronomy?” Fubuki raised a brow innocently,

“Astronomy is the scientific study of the physical universe beyond Earth, Fubuki.” Halara explains to their friend co-worker. “What you studied was Astrology, which is the study of the divination of the stars and connecting it to human affairs.”

“Oh, I see.” Fubuki sighed dejectedly.

”Don’t fret yourself. Astronomy and Astrology are mixed up many times because of similar terms. Even I will admit I had mixed up such terms back when I was a naive child.” Halara gives a small smile. “And you were correct in your Astrology knowledge, so your hard work paid off.”

”And that’s a cute operation name you made, Fubuki! I say we should use it.” Kurumi beams. 

Fubuki beams and cheers as she claps. “Yay!”

“I’m surprised you actually know about astrology! Or anything that concrete, for that matter,” Desuhiko muttered.

Which earned him a hit on the shoulder from both Kurumi and Halara. One of his shoulders is definitely going to get a bruise later.

“Going back on topic.” Halara takes charge around the table. “With Kurumi’s help, we’ll be able to plan our comrades’ birthdays much easier now. I’d say we start planning while Kurumi is still here. Unless your parents wish you home by now.”

“Don’t worry, my parents are working late tonight, so I can stay for about an hour or two more.” Kurumi pulls a chair up and sits where Yuma was just sitting. Which her legs accidentally kick against the ghost detective under the table. “Oh, sorry Vivia!”

Vivia just sighs and mutters his usual, “I wanna die someday.”

Everyone chuckles before getting into the planning. Kurumi relaying every shop in Kamasaki and Ginma they can go to. The plans and routes she and Yuma made for the next day to help avoid the trainee. Relaying every information they know about them to know what they can get. They keep talking until the darkness has engulfed the city with only the neon lights to help chase the shadows into their corners. And under the shelter of the Sun and Moon Hotel, the plans are prepared to be initiated for their teammates’ special days. 

As Fubuki (and now Kurumi) says, Operation Gemini Days is a go.

Notes:

Wahoo, my first multi-chapter fic on Ao3! This idea has been brewing for a long time. Ever since I learned Yakou’s and Yuma’s birthdays are right next to each other. And me loving their relationship so much (in a platonic/self-indulgent familial way), I cannot just not make a birthday fic of the two. And also add some Nocturnal Detective Family into the mix because yes! Heck, even the fic title “Operation Gemini Days” came as like an idea of what Yakou and Yuma would call their back-to-back birthdays.

Originally, I was actually going to post all five chapters over the course of May 19-23, but this chapter ended up being so much longer than intended (almost 6k!). So I decided to just post it a week earlier so people can take their time reading it. I’m hoping the next chapter will be out by the end of this week (because it’s most likely going to be another long one) and the rest of the chapters will be released next week (obviously on their birthdays) and hopefully be shorter than the first two. Fingers crossed🤞

Also, thank you to Kira AKA DraconicSparkle for beta-reading this chapter.

Edit: I actually forgot to mention that this idea was actually heavily inspired by an ask answered by Kumori_District from Tumblr.