Title: Nest

Summary: The Arcobaleno are stuck in a snowstorm when Verde goes into rut. Reborn is out of suppressants, no one else knows there's even a problem yet, and it's going to be super awkward when Skull tells them he's not actually an omega.

(SFW, just dumb Arcobaleno antics and some mention of sex.)

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Stuck in a luxury cabin in the Alps because of a snowstorm, the Arcobaleno are bored out of their minds, and they're either going to kill each other or brave the freezing weather to ski back down the mountain (and probably still die).

Sure, the holiday was nice, and the skiing was great (and now there are several more bodies buried under snow for Checker Face's latest mission) but it's been a whole week now and the tension is unbearable.

The Arcobaleno are all young, prideful, and far too powerful – not even mentioning how alphas tend to instinctively repel each other. They've known each other for about six months now and only spend time together for missions.

Sure, there are hints of a friendship starting up, but then Verde gets bored and starts trying to get cerebrospinal fluid samples for who knows what and that man doesn't understand the meaning of consent.

"No, Verde," Fon says when Verde reaches for something in his lab coat pocket.

Skull shifts until he's hanging upside-down off an armchair instead of across it, knees hooked over the backrest, and know he's going to get dizzy soon from all the blood rushing to his brain. Colonnello is sitting across the large living room, closer to the fireplace and surrounded by seventeen pillows, which he uses to occasionally hurl at people to get their attention.

Fon, Viper, Lal and Verde are sitting on the thick carpet around the short coffee table, playing an Italian card game that no one knows the rules to because Reborn is gone now and no one else here has been in Italy long enough to have come across the game.

"Let's play Fight The Landlord," Fon says instead.

Viper just throws down the cards and flops backwards, then creepily starts sliding under the table feet-first with their ESPer powers like someone is dragging them.

"And I'm gone," Lal says with a frown and decides to make a tactical retreat, standing up and heading back to the three-seater couch, picking up a glossy magazine on interior decorating or whatever. Her hands clench and relax repeatedly, making deep wrinkles in the pages.

Colonnello pegs a throw pillow at Viper but hits Verde's leg instead and can't duck fast enough to dodge the Lightning flame coated pillow to the face, the scientist too tense.

"Fuck!" Colonnello cries and there's something like a growl in his voice, clutching his nose. "Verde, you bitch."

"You hit me first."

"Come here, you gangly nerd-"

"Let's play Fight The Landlord," Fon says again, louder this time.

Everyone pauses at the sudden wave of pheromones in the already too-saturated room which is certainly not helping them to calm down - and then they see the smile on Fon's face.

"Um," Skull says and has to remind himself that he's immortal and Fon can't actually kill him. "Hey, Fon, maybe you should go and meditate."

Fon's smile widens because he's been doing nothing but meditating on and off for the last six days because there's certainly not enough room in this cabin to actually workout his frustrations. "Skull, would you like to spar with me?" he asks pleasantly but is still leaking aggressive, threatening pheromones everywhere.

Skull opens his mouth and quickly realises he's baring his teeth. "Is that Reborn calling?" Skull half sits up, then just kicks his legs sideways instead to flop out of the couch. He pops back up, staggers because he's dizzy, and hurries away. "Sorry, can't play, ask Nello."

Skull runs away to the sound of Colonnello's nervous laughter.

Skull passes Viper and Verde's room, Lal and Colonnello's, Reborn's solo bedroom because he's not afraid to pull a gun on someone to get what he wants, and reaches his own that he's sharing with Fon.

Skull caches the doorframe with one hand and swings himself inside to find the missing hitman kneeling beside Skull's bed, purple-coloured luggage strewn about.

"Senpai?" Skull asks.

Reborn's head snaps up, pupils blown wide. The hitman blinks a few times and stands up too fast. "Skull, where are your heat suppressants?"

"My what?" Skull says, forgetting that these people think he's an omega.

It's not that Skull wants to trick them, it's not malicious, it's just that a few weeks after that first, tense meeting, Reborn walked up and nuzzled into Skull's cheek, scent marking him like you're supposed to with an omega close to you.

And Skull...said nothing.

Because it was nice. Skull loves hugs, and kisses, and being scented is so comforting and Skull can smell Reborn for days after. It's fantastic.

Skull knows Reborn did it as a power play, to show he's stronger than Skull, to dominate a Cloud and prove he's the prime alpha in this somewhat-pack. Reborn especially seemed a bit taken aback by how Skull happily leaned into it, and then started chasing Reborn around for more.

And then the others, after realising Skull wasn't a 'normal' Cloud and won't tear their heads off for presuming to scent him, well the others joined in. After all, everyone knows omegas need constant physical affection and Skull had already admitted he didn't have anyone as a support structure because he kept moving around so much for his stunt jobs.

(Skull admitted this before his brain kicked in and he realised they were implying how omegas needed approval and trust to function and were checking in on him.)

Anyway, it was even better when everyone joined in! Skull gets all the hugs now! Sometimes they'll come over to his house even, instead of just meeting at the Arcobaleno manor. They'll come over and cook him food and hang out.

It's also a bit convoluted, really, because no one wears their real scent. Not in the Mafia, where your scent can mean being tracked back to your crime.

Lal and Colonnello have military grade scent blockers so they smell like the rest of COMSUBIN, Viper doesn't smell of anything, Verde smells different every day, while Fon is all ash and blood from a Triad-made blocker and Reborn smells of pure sunlight because he overpowers his natural scent with Sun flames.

But that's fine too because Skull isn't an omega, and he doesn't latch onto scents - he can't even tell if one is fake so he's not harmed by it. Skull recognises them by these odd smells now, and whenever he passes another COMSUBIN soldier on the street he'll get weirdly happy, which he thinks is hilarious.

Skull himself has always been told he smells of metal and gasoline, which is definitely not a healthy omega scent, and is actually considered a rather threatening alpha smell or something from an abused omega - but the others probably think it's just smells that have rubbed off because of his stuntman jobs and his car obsession.

(Do they assume he's got trauma? The tattoos and piercings are fashion sense, not daddy-issues.)

To be fair, most Mafia alphas look like Reborn, and have at least a couple dozen to their body count. Skull is normal height for a beta, looks like the Joker, but is perfectly harmless otherwise and pretends he doesn't understand personal boundaries so he can snuggle with people.

He does kind of act like an omega, and with all these alphas around, it's no wonder they give into the protective instinct - because otherwise they'd give into the instinct to rip each other apart.

So in the end they don't really smell like each other, and no one quite knows who is an omega or alpha or beta because that information can be used hurt them, but they're still close. Sort of. They all scent Skull but not each other, and only because they think Skull will become depressed if he doesn't get enough affection, but it still counts.

Maybe playing house is the best way to put it.

"Yeah," Skull says, after far too long of a pause. "Um, heat suppressants. Yes. Actually, I'm not close yet, so I didn't think I needed to bring any medication with me."

Reborn stares. "Suppressants are daily pills."

Fuck, I'm an idiot. Skull laughs too loudly. "Yeah, I was joking. I have them."

"Where are they?" Reborn snaps, out of what little patience he had left. "Skull, just - where did you put the pills?"

Skull is trying so hard to think of an excuse that his brain goes completely blank because he has the self-preservation instincts of a goddamned leaf. However, this also means he finally realises how off Reborn is acting.

"Why do you want them?" Skull asks hesitantly.

"I don't," Reborn says. He straightens up, sets his broad shoulders back, looms over Skull. "If we're going to be locked in here, I want to make sure an accident doesn't happen, like you going into heat."

"That's pretty unlikely," Skull points out.

"Not if someone goes into rut and triggers you," Reborn says this with a relaxed tone, as if just make vague statements.

"Is someone going into rut?"

"I don't know," Reborn answers casually. "Omegas are more sensitive to that kind of thing, though." He pauses. "So. Skull, can you tell if someone is going into rut? Right now?"

Skull looks away and then back to Reborn. "I don't know what the right answer is."

The next thing he knows, Skull is slammed up against the wall next to the door, Reborn gripping his collar, leaning so close Skull can feel the hitman's body heat.

"Skull," Reborn snarls. "Someone is going into rut and it will trigger your heat. You need to take ten of the daily pills to counteract that until we can get out of this godforsaken cabin. Where are your suppressants?"

"I didn't bring them," Skull says apologetically, soothingly rubbing his hands up and down Reborn's sides. "Reborn? Sunshine? Are you going into rut?"

Reborn snarls again into Skull's face and then wrenches himself back. The hitman turns around, takes several deep breathes, and when he turns back there's no sign of distress anywhere.

Reborn smirks lightly and smoothes down his suit jacket. "Well then, I guess we have a problem."

"I - I'll be fine," Skull tries because this fake omega thing has never gotten serious before.

Reborn grabs Skull's upper arm and marches him out and back down the hallway to the main room where everyone is still lounging around, though Fon is now sitting on the coffee table and Viper has turned into a pile of tentacles underneath it with Verde missing – maybe eaten by Viper.

"Where's Verde?" Reborn asks.

"Bathroom, I guess," Colonnello says lazily, rebuilding his pillow fort.

"Someone here is in rut," Reborn announces. "Just the early stages. Skull can sense it because he's an omega."

Skull can do no such thing, but Reborn has clearly been freaking out about this so Skull isn't going to say anything. It does explain why everyone is so on edge right now because they must be going into rut too.

Lal sits up and looks around, eyes lingering on Colonnello and Fon. "Alright. So, are any alphas here aware of any issues with their hormone treatments?"

No one says anything.

Lal sighs and drags a hand down her face. "Never mind. Skull, do you-"

"He doesn't have suppressants," Reborn cuts in. "No medication at all, not even cologne to maintain his fake alpha scent."

Skull makes an understanding noise in the back of his throat because now he understands why no one has even suspected him of being alpha from his scent.

"What?" Viper blurts out, re-emerging from under the table as a human again. "No suppressants? Omegas carry that shit around religiously. Shouldn't you have a backup set as well?"

"Sometimes omegas forget," Reborn snaps, dropping his calm facade. "Not like alphas, who take a shot every three months, pills are daily and sometimes you lose count."

"Yeah!" Skull chimes in because that's kind of unfair, isn't it? "What Reborn said! Sometimes you lose count."

"But you didn't bring anything," Fon says.

"Maybe it ran out!" Reborn finally drops the death grip on Skull's arm to plants hands on hips. "Maybe he brought it, but it ran out because of this stupid snowstorm blocking us in, and he thought it was fine because he wasn't expecting a fucking alpha to go into rut."

"Ah," Verde says, stepping up behind Reborn and Skull. "Good, you already know. My experimental hormone treatment didn't cause the usual fatigue and chills but that seems to be because it didn't work at all." Verde turns to Skull. "Do you have enough-"

"He doesn't have any pills," Viper answers before pursing their lips. "And, it seems, neither does Reborn."

Verde looks down at Reborn instead. "So we'll be raping you as well."

Colonnello slaps a hand to his forehead. "Verde, you autistic fuck."

Verde scoffs. "I have Asperger's, and I'm very high-functioning. I also happen to be simply pointing out the obvious, though perhaps not as delicate as your precious sensibilities require."

Reborn can't answer because he's holding his breath to not smell Verde's building scent of mint and petrichor. If Reborn could answer, he'd explain that he is very willing and that everyone else is also going to be very willing after Reborn demonstrates just how impressive he is as a lover.

Fon is not the only one who rolls his eyes at the sultry, smug expression on Reborn's face.

Lal slaps the magazine down onto the floor and stands, ready to start preperations. "Reborn, Skull, you two barricade yourselves in. Maybe if we remove you, Verde's rut still isn't strong enough to trigger you. You'd be able to fight the rest of us off."

Reborn let's out a frustrated breath and his shoulder slump. "It's too late. I have maybe an hour until I'm non-responsive, and I'm using Sun flames to even think clearly right now. Verde's been in pre-rut since last night, and I thought I was imagining it because Skull didn't say anything."

Skull stares at the fancy painting of fruit and pretends he can't feel everyone staring at him. He likes to think he lasts more than ten second before caving under the pressure but probably not.

"Okay, so maybe I'm not an omega," Skull says.

Colonnello throws a pillow at him. "It's been months since I started scenting you. And - wait, you actually smell like metal and gasoline? Jesus, I thought you bought that cologne to scare people away."

"I smell fine," Skull splutters, offended. "It's fine, I like it."

Lal holds up and to stop the argument continuing on forever like it usually does with Skull and Colonnello. "Before we make solid plans, does anyone else want to come up and throw in any more surprises?"

"I'm a beta," Fon says.

Reborn looks Fon up and down. "No you aren't."

"And yet I hear you're an omega?"

"Touché."

Fon smiles. "I'm a beta, but I have been on alpha hormones since I was six years old, as is traditional in the Triads. I have pseudo ruts, but they are far and few in between. Maybe I will remain clear headed like a beta, perhaps I will cause some damage."

Skull mouths 'some damage' and Fon shrugs.

Lal turns to Viper next.

Viper grumbles. "I won't go into heat or rut but my head still gets messed up. I can't do anything."

"Colonnello and I are alphas," Lal finishes last, but it's not like those two were trying to hide anything either. "Reborn, are you okay with mating or do you want to try and attempt to hide in the walls like you usually do? Either way, I'm sure Verde can make something like a collar quickly to keep us from biting you."

"Mating with all of us?" Skull cuts in with a bit of a wince. "That's a lot though."

"I don't mate when I'm in heat," Reborn scoffs. "I nest. I nest hard. And I will destroy you, even if I do want sex, because I'm too busy nesting."

"But after you nest," Fon begins. "Reborn, you might need to pick someone, even if it is just for now. I'd be able to protect you from anyone else just on instinct alone but you'd need to be okay with mating with me and not try to fight me."

"All I do is build a nest," Reborn repeats, trying to make them understand. "I literally don't have a choice. If you interrupt me, I'll kill you and I won't even notice. I get obsessive and it needs to be perfect."

Lal shares a look with Colonnello. "Fine. Reborn, take any supplies you need to the furthest bathroom since it has the strongest door. We'll try to barricade you in. We'll then lock ourselves up in our bedrooms, maybe I can knock a few of you out with Rain flames but it won't last the whole twenty-four hours. If something does happen, well, we can talk about children later."

"Oh, shit, children," Viper says.

A normal omega already has two or three babies in one go. A strong omega has up to four. Reborn, the World's Greatest Hitman with the most powerful Sun flames, probably has a litter of babies.

"Can I ask about consent?" Skull asks hesitantly. "Because I know it's going to happen anyway, but, um."

"I'm fine with it," Colonnello offers up, and ignores Reborn's snide remark about the little virgin soldier saving himself for Lal.

Everyone else agrees in vague terms because they're not against the idea but it is going to be uncomfortable since it's pure instinct. They would have rather not done it like this, but now that it's happening they don't mind. It's not like they haven't thought about it since Reborn is such an outrageous flirt.

Reborn rolls his eyes. "Yes, I love sex. You already know that. Yes, I'd sleep with you all regardless. No, I don't mind gangbang. Pull my hair and I'll slit your throat. I love getting my dick sucked and seeing lipstick smeared over it-"

"Thank you!" Verde says loudly. "Thank you, Reborn. Now I'm really feeling the rut."

"You're welcome." Reborn winks. "Actually, maybe we should start the sex now before I get heat-dazed and start building."

"It doesn't matter how much you like building, we're probably going to drag you away from it to mate."

"You're really not understanding how personally I take nesting," Reborn insists.


Twenty-six hours later, Skull shudders alive and blinks up at the ceiling of the hallway.

He sits up and finds the other Arcobaleno in various stages of bleeding, clothes torn off and vicious bite marks everywhere. Skull crawls around to check that everyone is still breathing and then uses liberal help from the wall to stand.

Skull gently nudges the bedroom door open and finds a naked and scratched up Reborn perched in the centre of three mattresses pushed together, the bedframe shattered against one wall. All the blankets and pillows and clothes (stolen from luggage as well as torn off their bodies) and really anything soft at all woven together in the most magnificently styled nest Skull has ever seen with cute coloured coded sections.

Reborn is half-unconscious, weakly kneading at a bump in the blanket, wearing the make-shift collar Verde made but there are plenty of bite marks everywhere else that are already half healed.

"Sunshine?" Skull calls out hoarsely. He swallows and it doesn't help. Broken neck probably. "Reborn? How are you doing?"

Reborn stares at the bump and keeps kneading. It's probably Skull's motorbike helmet under there.

Colonnello rolls over with a groan. He's the least injured since Lal knocked him out with Rain flames, because even in her half-blind rut she wanted to protect Colonnello from Reborn after the hitman turned a drawer handle into a shank.

Thank fuck they hid all the guns before it started.

Skull is also thankful that he and the other alphas didn't turn on each other either to fight for the mating, but that's probably because Reborn was such a threat they couldn't divide their attention.

Skull didn't know Reborn could get that strong. Well, Skull knew the hitman was strong but goddamn that was a whole other level.

Reborn was jacked up on Sun flames so he didn't go limp and dazed like most omega, plus he was acting like the Arcobaleno were going to knife his non-existent children or something the way he went snarling mad when they touched his nest.

Poor Fon got the worst of it because he just doesn't know when to stay down. He's the only one who actually managed to fuck Reborn and now he has the battle scars to prove it.

Colonnello staggers up and into the bedroom. Reborn doesn't react, only the last dredges of the heat-daze keeping him going. The blond goes in from behind and grabs Reborn around the waist, dragging him backwards. "Come here, baby born. Time to heal all your poor victims."

Reborn makes a quiet distressed noise but doesn't -or maybe can't- fight now that he's this exhausted.

Colonnello dumps him in the middle of the nest and goes back to start dragging people inside with help from Skull. Verde's giant, lanky body gives them the most trouble, though Viper starts turning liquid mid-way and they throw the Mist onto the bed in a panic.

Everyone is arranged around Reborn, touching the hitman with skin-to-skin contact and the Sun flames quickly start leeching over.

Colonnello sits on the side of the low mattress and sighs heavily. "Holy shit does that omega nest."


They spend another three days in the cabin despite the storm dying down, partly because everyone is still mentally exhausted, but mostly because Reborn now knows he can fuck them and wastes no time breaking them in.

"Six very attractive lovers who I can use anytime I want?" Reborn laughs, sitting up against the wall on what is still just three mattresses shoved together for his nest, legs covered in the other sleepy Arcobaleno. "It's going to be ages until I get bored of you."

Colonnello's head jerks to the side like he was actually hit by that backhanded compliment. He groans in pain and rolls around dramatically until Reborn kicks his shoulder and he just flops over Lal.

"I like nice alphas," Lal muses, head on Reborn's thigh. "Cute, obedient ones who listen to me. So why am I in bed with you people?"

"I'm cute and obedient," Skull says happily against Reborn's stomach, lying sideways across the nest.

"No the fuck you're not," Viper scoffs, up on their elbows over Reborn's ankles. "Skull, I don't know who you think you are, but you are a full fucking freakshow who also happens to say please and thank you."

"No I'm – what – what do you mean?" Skull splutters, rolling over and bumping into Fon.

Verde ticks things off on his fingers; "The makeup, the tattoos, the clothes, the cackling laugh, your driving, the killing yourself habit, you steal our clothes to keep our scent, I know you marked us with Cloud flames, you ate someone in front of me-"

"I was-" Skull tries, sitting up. "No, I was shot in the head, it doesn't count. I was missing half my brain."

"You were missing half your brain and still had the capacity to eat someone alive," Verde finishes. "Oh, look, I ran out of fingers."

"I think that's pretty cute," Reborn allows, petting Skull.

"You know you're a Sun, right?" Fon asks, arms folded over one of Reborn's knees, chin on top. "I'm just checking that you know that."

"What is that supposed to mean?" Reborn complains.

"No, nothing. Just checking."

Reborn tsks. "It goes hitman first, then incredible sex god second, fashion icon third, and finally a Sun user."

"Where's 'omega' on that list?" Viper asks.

"It's a sub-clause of 'incredible sex god'."

Lal is pinching the bridge of her nose. "I am so done with you people."


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A/N: As tribute to all of you who comment to ask me for poly!Arcobaleno. I have been noticing more Arcobaleno-centric fics around here and it's fucking fantastic!

Leave a comment! I want to know if I should do more relationship-based fics or if you still like action and plot better.