Hi! Welcome to my *30th!* omegaverse fic! I wanted to do something different to celebrate that milestone and as I've never actually written Dazai in heat, my mind finally decided it was time to brave it (totally ignoring both a poll I ran and my other plans) hope you enjoy! ^.^

This takes places four years after the events of Beautiful , I'm aware it's long, so if you're not ready to read to sum up: Dazai and Chuuya had a one night stand, did everything right and Dazai got knocked up (abortion etc not an option due to weird omega things (aka I'd have no plot if it was an option lol), Chuuya wasn't ready to be a dad so Dazai raised them alone, eventually joined ADA, Kunikida met his kids when they were 5 and realised Dazai is beautiful, they slowly start dating, the kids encourage Kunikida to move in and they marry when the kids turn 11, with them asking Kunikida to adopt them (Chuuya was known about but not in their life till they were 5ish, and took more of an uncle role)

For those of you who have read it, this was supposed to be in the main fic and took place much earlier, and was originally the reason Dazai decided to propose (but the moments with the kids, worked better in the end)

Cwtch/Cwtched/Cwtching - It's a Welsh word, here it's meaning a cuddle or hug (but like nicer, cosier and more personal than a hug if that makes any sense?) The word can also mean a small cupboard/cubbyhole

Dazai was waiting in bed when Kunikida finished his night time routine, he had worked late and the kids, now fifteen, were long asleep.

"I didn't think you'd still be awake" Kunikida greeted his husband with a kiss, slipping in to bed next to him.

"We've barely seen each other this week, and I didn't want you to come home to a dark house again." Dazai replied pulling Kunikida in for a cwtch.

"One more day and we've got the weekend free," Kunikida smiled. "Do we have anything planned?"

"Well…. Chuuya rang earlier, he's got some time off and asked if Tabitha and Dante wanted to spend the weekend with him, as it's the school holidays, if you're okay with that?"

"Why are you asking me?" Kunikida asked, confused.

"Cos you're their father, and you have as much say in what they do as I have. C'mon it's been four years, surely you've learnt that by now." Dazai smiled.

"I know that, but I never feel like I should have a say in what they do with Nakahara-san" the 'as he's their biological father' was left unsaid.

Dazai pulled Kunikida in for a kiss, "You are more a father to them, then he ever was or will be. Now, are you happy for them to go with him or not? I told him I had to check with you first."

"Yes, it's fine, they'll have fun with him, and they're old enough to be left alone for a bit if he needs to go to work."

"Perfect, I'll text him now." Dazai sent the message, getting a quick reply. "He says he'll pick them up on Saturday morning about nine and bring them back on Monday around lunchtime?"

"Sounds good." Kunikida smiled. Dazai replied to Chuuya's message, before putting his phone on the nightstand.

"So, on to our plans for the weekend," Dazai grinned, "my heat is due to start on Saturday, and…." Dazai took a deep breath, "I'd like to spend it with you."

"Are you sure?"

Dazai nodded, "Well, with your pill nothings happened outside of my heats, and it's been fifteen years since…since that heat. You've been by my side for ten whole years, and have patiently let me work through my feelings and fears. I'm ready to share this final part of my life with you." Dazai smiled, "You make me feel safe and if I'm honest, my last few heats, I've found myself looking for you," Dazai blushed.

Kunikida kissed Dazai, "We'll go as far as you feel comfortable, okay? We can stop at any point, and I won't say a thing."

"Thanks Doppo" Dazai kissed him, "Night." He cwtched into Kunikida and turned off the light.

There was a knock on Yosano's office door,

"Come in"

She was surprised to see an embarrassed looking Kunikida,

"Please sit" she instructed, smiling.

"If it's not a good time, I can come back…" now he was there Kunikida started losing his confidence.

"It's fine, remember anything said in here, doesn't leave."

Kunikida sat, sighing.

"Dazai's ready to take the next step."

"Next step? You already live together and you're married, what exactly is next?"

"His heat."

"You still haven't spent a heat with him? Please tell me you two at least have sex?"

"Yes, the kids are out of the house a bit more now, and Dazai's getting over his fears. We haven't bonded either."

"Doing everything right and still managing to get pregnant really broke him, didn't it?" Yosano sighed.

"Yep, but he talked about it, and went to therapy, and we seem to be making good progress."

"Well the pill you are on now will be fine for his heats to. I'll be honest I thought you two had already spent those together, as Dazai's been off his heat suppressants for a while now."

"Because I'm there, he felt safer having his heats because Tabitha and Dante would be fine, and he'd been on suppressants for well over ten years I think he'd had enough of them. I don't blame him."

"So, what exactly are here for?" Yosano asked.

"Well… I… I know…" Kunikida took a deep breath, blurting out the next part "I don't have a knot."

"Well I'd hope not considering you're a Beta," Yosano laughed

"Yes, but how do I get him through a heat without that? I've seen the toys he uses, a good half of them have knots and I don't want to make his heat worse, by not providing the optimum umm experience." Kunikida blushed.

"Ohhh I know what you need, do you have anything else to do today?"

"No,"

"Let's go shopping then" Yosano grinned.

Half an hour later, and they were in sex toy shop in a local shopping centre, this particular shop specialised in Omega needs.

"Why is there so much?" Kunikida asked, both amazed and terrified at the array of items.

"A happy, healthy Omega, means a happy life and the Alpha and Beta's dating them are very happy to spend to ensure that happens."

Yosano stopped and pulled an item from the shelf,

"Aha! This is what I'm after,"

"This? But it's just a cuff?"

"Exactly, you put it around the base, then it mimics an alpha knot as you fuck him. This one claims to be as pleasurable for you as it is for him."

"Great. As we're here, I took some pictures of what he's already got, I thought I could get him some new ones? As unless he's replacing them with the exact model, he's some of the toys a long time."

By the time they were done, Yosano had helped Kunikida pick out two new toys for Dazai's heats and array of items for outside of his heats, claiming that as their children were getting older, they'd have time to experiment. Kunikida hadn't stopped blushing, but he hoped it would be worth it. He got home after Dazai and quickly ran upstairs to hide the items; he'd mention them before bed so they weren't sprung on Dazai during his heat.

(He forgot)

Dazai's heat kicked in just as Chuuya arrived to pick up Tabitha and Dante. As they were getting older, Dazai didn't try to hide away when his heat was starting, if either of them or their friends presented as Omega's, he wanted them to know the signs. Seeing the state Dazai was in, Chuuya told them he could drop Tabitha and Dante off with one of the agency members or keep them another night, if it was needed. Kunikida thanked him, and took Dazai upstairs.

First up was a bath, Kunikida didn't know why, but Dazai insisted on a far too hot bath to start his heats off. He always required supervision at this stage, the heat of the water combined with his temperature increasing because of his heat meaning he would drift off and almost drown.

Kunikida stripped Dazai and got him into the bath, the omega floppy and treating him to many kisses before he got into the bath,

"Mmmm you used the citrusy one, good choice Kunikida-kuuunn" Dazai smiled, as he relaxed into the extra long bath. Kunikida set a timer as Dazai got settled, through trial and error he'd found seven minutes and thirty-five seconds to be the optimum time for Dazai to bath. He'd leave the bath suitably relaxed but not almost passing out from the heat.

As Dazai bathed Kunikida, pulled off his pyjama top, leaving the shorts on. The timer beeped and Kunikida pulled the plug on Dazai's bath, letting the water drain fully before wrapping Dazai in an extra soft and fluffy towel that he'd bought especially for his heats.

"Kunikidaaaaa where's all my waaater?" Dazai whined.

"It's time to go into your nest." Kunikida told him, having learnt that simple explanations were easiest when Dazai was in this mood. He rubbed the towel so Dazai would dry a bit before tugging on his middle to encourage him to stand, bending slightly so Dazai could use his shoulders as support as he got out of the bath. Safely out, with the towel wrapped around him like a strapless toga, Dazai pulled Kunikida in for a cwtch and started kissing him. They were the sort of kisses that were hot and full of promise. If Kunikida had less control, he would have followed the promise and fucked Dazai on the bathroom floor. Instead, Kunikida untangled himself from Dazai and quickly dragged him across the short landing into Dazai's nest-room. The room was small, with all the pillows Dazai had against the one wall there was about a foot left at the bottom when Dazai was stretched out, a set of drawers was on the right-hand side, and a window on the left. The items from his nest were folded in the centre of the room. Dazai stopped still when they got into the room, the cooler air and brightness bringing him back to reality, he turned to face Kunikida,

"I need a minute."

"Take all the time you need. I just need to grab something from our room okay?"

Dazai nodded, taking a deep breath, Kunikida placed a light kiss on his hand, before leaving, pulling the door ajar.

Kunikida took his time grabbing the items – two new toys, the fake-knot cuff and some special body lotion he'd been waiting to try out. He also checked his medication organiser, afraid he'd somehow forgotten to take his pill today, he'd hate to let Dazai down on the one thing he could actually do to help. They had agreed to not bother with condoms, they were both clean and they knew Kunikida wouldn't be able to keep up changing them and meet Dazai's heat demands. He double checked the bath was empty and that the front door was locked, they weren't expecting anyone, but Kunikida wanted that feeling of safety for both of them.

"I'm ready!" Dazai yelled, as Kunikida was making his way back upstairs. Kunikida stopped in front of the door, the new items in his hands. Dazai's scent – the strawberry sweetness of summer was strong. Kunikida didn't know if Dazai had made it stronger so even a Beta like him could smell it, or if he was just that relaxed. He knocked on the door,

"Dazai?"

"Come in Kunikida-kuuunnn" Dazai replied, excitement in his voice, "I'm ready for you."

Kunikida pushed the door open, Dazai had pulled the curtain shut, the blackout fabric hiding the sunny day, and turned on the two lamps he'd recently added to the room, giving the place a warm glow.

Dazai was in the middle of his nest – a thick blanket underneath and a ring of clothing (robbed from Kunikida during the week) and spare blankets and towels surrounding him. He'd spread his legs, instinct taking over and telling him to present for his partner.

It was lost on Kunikida.

He shut the door behind him, placing the items on the floor. He knelt by the side of Dazai, careful not to get in the nest yet, and kissed his husband.

"You look beautiful for me Osamu."

"Why aren't you in my nest?" Dazai whined.

"I wasn't sure if I was allowed yet."

"Get in." it was almost a growl.

Kunikida moved, grabbing the pot of body lotion before settling at the bottom of Dazai's nest.

"This is a lovely and comfortable nest you've made Osamu." Kunikida complimented him, feeling proud at the gleeful reaction it got.

"I made it special for you." Dazai grinned. "Why haven't you touched me yetttttt?"

"I'm getting there" Kunikida opened the body lotion and started rubbing it into Dazai's toes, working it up his foot and onto his legs.

"What…what are you doing?!" Dazai asked surprised

"My scent is quite weak and this cream apparently amplifies it, and I thought you'd like the pampering."

Kunikida didn't want to tell him that he wanted to take this slow, that he knew Dazai liked his heats hard and fast, but wanted to do something so different, that it would hopefully stop the fears of the past ruining it.

"Your scent isn't weak Doppo, this room is full of your bright citrusyness alreadahhhhhh" Dazai moaned as Kunikida worked the lotion into a sore spot.

Kunikida continued up Dazai's body, adding some kisses and constantly praising and complimenting his husband. Dazai's scars meant nothing to Kunikida, his own body had its fair share, and he'd found Dazai was happier if they were ignored. (Just like he ignored Kunikida's)

Kunikida stopped at Dazai's neck, swapping hands for lips and kissing up to his mouth. Dazai kissed back eagerly, they pulled apart,

"Why don't you put that mouth to better use?"

"Not yet, I'm only half done."

"But Kunikidaaaaaaa" Dazai whined,

"I promise I'll make it worth the wait…okay?" Kunikida kissed him before returning to rubbing lotion into Dazai's body, switching to the other side.

"Fine."

Kunikida laughed.

"Hmmm why don't I tell you what I think would be fun in the future?" Kunikida continued before Dazai could answer, "I can pretend to be your omega, at your mercy whilst you just fuck me with no thoughts other than our pleasure, not when you're in heat of course, but next time we have a free afternoon."

"Hmmm that does sound good, but first you need to hurry up and fuck meee!"

Kunikida was on Dazai's knee, and laughed,

"Just got to get to your toes. How are you feeling?"

"Frustrated." Dazai glared at Kunikida as he said this, "maybe a little relaxed to."

"Good."

Kunikida finished with the body lotion, doing it up and setting it aside. He pinned Dazai to the nest and started kissing him,

"Finally!" Dazai groaned, as Kunikida started kissing down his body, taking his dick in his mouth.

Dazai moaned, coming almost immediately, the teasing and his heat making him extra sensitive. Kunikida had no choice but to swallow, grabbing a bottle of water from the side to wash it down, before forcing Dazai to take a drink.

"More, Doppooooo" Dazai started fidgeting as he started producing slick.

Kunikida nodded, teasing Dazai's entrance with a finger,

"You don'tahhhhhh….have to…" Dazai didn't stop moaning as Kunikida quickly added more fingers, he knew Dazai didn't need preparing, he just wanted to see what it felt like. He'd watched over his husband in heat many times, but had never gotten to touch. He knew Dazai's heat would go smoother if he was knotted on the first fuck so he quickly slipped the cuff on, biting back a moan at the strange sensation.

He positioned himself at Dazai's entrance, kissing him,

"Ready?"

"Yessss"

Kunikida slowly entered him, Dazai moaning at the sensation,

"So close…."

"Already?"

Dazai nodded, "I…ahhh I'm sensitive when I'm in heat, and don't have my usual limitations."

Kunikida wrapped his hand around Dazai's dick, bringing him to orgasm as he finished entering him, the cuff catching as Dazai came.

As he came down from his high, Dazai started panicking, he felt the fake knot and started sobbing and trying to push Kunikida off.

"No, no, no, not right. You're a beta, get it out, get it off, I don't like it. No, no,"

"Shh-shh it's okay, Osamu…stop, Dazai! Stop moving." He grabbed Dazai's arms, making him stay still so he could pull out.

"Okay, it's off. I'm sorry, I thought it would help." He pulled Dazai in for a cwtch, the tears had stopped. The fear had pulled Dazai out of his heat a bit, so he was more rational.

"It should have, but even my omega side knows my mate is a Beta, and I think a knot-less fuck will actually calm my heat." He rubbed his face into Kunikida's neck, taking a deep inhale of his scent.

"I bought some new toys for you to, they're like the other items you own."

"Not today, I have an err ritual for new toys, and now isn't the time for that." Dazai replied, "but thank you for thinking of me," Dazai kissed him, long and slow, "I think we can try again now." Dazai smiled, letting go of Kunikida and settling back into his nest.

Kunikida kissed Dazai as he entered him, both moaning at the sensation, Kunikida stilled to give Dazai a moment to adjust.

"I'm fine" Dazai murmured, kissing Kunikida.

Kunikida started at a slow pace, the sensation of Dazai's slick unlike anything he'd ever felt.

"Faster" Dazai moaned, as Kunikida hit his prostate.

It didn't take long for them to come, Kunikida moaning out Dazai's name as he came first.

"Don't…" Dazai took a moment to catch his breath, "don't pull out, just lie on my chest"

Kunikida lowered himself, gently so he was half lying on Dazai

"I'll move when you're ready."

"How was your first time fucking an Omega in heat?"

"Nice, you feel really good Dazai."

"I'm ready to go again… take it slow this time…" Dazai instructed

"Already?!"

"Awww the beta not up to it?" Dazai smirked, even in heat he could still tease Kunikida,

"I can always leave you know…." Kunikida's tone was joking, as he was already shifting so he could start again.

"No fair!" Dazai pouted

Kunikida kissed him, "I'll be here till the very end. I promise," as he spoke, he thrusted in and Dazai moaned.

The next few hours were a blur of different positions and cwtchy breaks for drinks and snacks. At some point Kunikida had given in and started using Dazai's toys, his body couldn't keep up with his husbands demands. Kunikida was currently cleaning the sticky mess from Dazai,

"Mmm such a good Kuni-kuuunnnn, taking time to make me allll clean." Dazai captured Kunikida's lips in a sloppy kiss, pulling Kunikida closer to whisper in his ear, "just in time to get me all dirty again."

"In a minute, oh you're getting hot."

"I'm in heat silly Kunikidaaaa and it's nearly time for the best bit"

"Best bit?"

"Hmmmm the bit where my mind just goes bye-bye and alll I want is you and guess what?" Dazai didn't wait for answer, "you're here! How fun is that going to be!"

Kunikida laughed, he'd never seen Dazai drunk, but he was sure his heat-drunk self wasn't far off it.

"Yes I'm here," Kunikida threw the towel into the corner and pushed Dazai back down into his nest,

"Nuh-uh, I want to do something else."

"Okay," Kunikida moved back, sitting in front of Dazai instead. "What do you want to do?"

"You." Dazai giggled.

"Me?" Kunikida asked, confused.

"Yep!" he turned slightly to grab something from under the pillows, looking triumphant when he found the bottle of lube, "I…I had it for later..later in my heat…but it'll be good for you."

"I..a…are you sure?"

"Kunikidaaaaa please."

"Okay, but if it's not right, then we can do something else okay?"

Dazai nodded, eager to fuck his husband. Kunikida reached for the lube but then had a better idea.

Dazai was still producing slick, his ass and blankets wet with it (and Kunikida's come from earlier) Kunikida leant forward, kissing Dazai, and wetting his fingers with the slick, and went back to sitting. He spread his legs as Dazai watched with eager eyes as Kunikida opened himself up using his slick. Dazai came with a moan from the sight alone.

"You like that huh?" Kunikida asked, gathering more slick and moaning as he added another finger. Dazai didn't let him add a third, practically pouncing on him,

"My turn"

It took a minute as they were both too eager, but Kunikida was soon in Dazai's spot, moaning as his husband thrust into him, Dazai hitting his prostate with each thrust.

"Thisisamazing. Best ahhhhhh. Heat….. ohhh ever." Dazai panted out as he thrust into Kunikida, who was still a moaning mess underneath him.

"Gooohhhood"

"Biteme…Markme…please….soclose." Dazai moaned slowing as he waited for Kunikida's reply.

Kunikida kissed him, "Show me your neck."

"Yesssss" Dazai moaned, turning his head so Kunikida could reach his scent glands.

"Love you" Kunikida whispered, he came and bit down on Dazai's neck, the action pulling Dazai over the edge, coming with a shout of Doppo. What felt like seconds later, but was actually a few minutes, Dazai was riding Kunikida, and the high of their new bond.

The next few hours were a mess of them switching as Dazai chased the pleasure and high only his heat could bring. Kunikida getting swept along, wanting to give his mate the pleasure he wanted.

As Dazai's heat faded, Kunikida opened the curtains, and they had one final round as the sun rose outside. Kunikida taking his time to ensure Dazai had nothing but love and pleasure to remember about their first heat together.

The following morning (Monday) they woke up in their bed, after a very long sleep. Dazai was cwtched into Kunikida.

"I think you broke me Osamu." Kunikida grumbled, sounding almost like his husband.

"Oi, I was the one in heat, that's my line." Dazai laughed. "It's a shame the kids are still with Chuuya, I'm sure they could've been bribed to make us breakfast in bed."

"Mmm I'll move soon, lets stay here for now." Kunikida pulled Dazai closer, "so how was it?"

"It was the best heat I've ever had, thank you." Dazai placed a light kiss on his lips, "and thank you for bonding me, I know I sorta sprung it on you…"

"I don't care, it felt right."

They cwtched in silence for a while, before Dazai spoke

"I've never fucked someone else when I've been in heat before, can we do it again, next time?"

"You liked it?"

"Yeah, it's a different sort of pleasure and oh was it good." Dazai smiled, "I'm glad we waited, you make me feel safe and I… I'm not scared, I know whatever happens we'll face it together and I never thought I'd ever feel so content after a heat, so thank you." Dazai kissed him, slowly pulling away. "I love you so much Doppo"

"I love you to, Osamu." Kunikida smiled.

They cwtched closer, content and happy, before falling back asleep, a smile on their faces.

A/N You can also find me on Twitter and AO3 as Darke_Faerie