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It was a misconception that all Omegas nested from the time they present.
Of course, all Omega's create a safe space to sleep in and manage their heats.
But a real nest is something only an Omega who truly feels safe and comfortable will build.
A nesting Omega is one who knows they are protected.
Mori had never built a true nest, had never felt the want or desire to do so, had never been with an Alpha who awakened that instinct in him. He'd always been content with a few more pillows and blankets than his large bed reasonably required.
He doubted his presence inspired the instinctual and protective nature of any of the Alpha's around him to come out… Mori was not a typical Omega: strong, abrasive and lacking all the maternal instincts he should have.
Driven and ambitious, he was willing to sacrifice anything and everyone around him if it meant attaining his goals. Mori had always known the chances of finding a comparable Alpha were slim to none… he was okay with that.
Truly, he was.
Although, like all things in life– that was subject to change.
- - -
Normally, when Mori would take Elise shopping, he bought very little– if anything for himself, his soul focus being her.
Today, while the two were out, he kept getting distracted, feeling the softness and warmth of the pillows and blankets he passed. It wasn't until the shop assistant helping them brought it up, did he even realize what he was doing.
"Looking to redo your nest?" She asked, giving him a knowing smile, pulling him back to reality.
"Huh? Oh, no! I–" he began stuttering out, not even sure himself what to say. Mori had no experience with nesting, never thought too far beyond what he deemed comfortable to sleep with… hell, he only owned two things that could even be considered 'comfort items' that he only pulled out while in heat.
The shop assistant just smiled knowingly, "it's fine, let me help you find something to your taste, I'm sure your daughter will be a while with the tailor, getting all her fittings for the lovely dresses the two of you picked out."
Nervously, Mori nodded, allowing the woman to pull him over to a completely new section of the store, "What colours do you prefer? Bright, dark or muted colours?"
Having never given such things much thought, Mori had to take a moment and think, right now his sheets were mostly black, with a few shades of dark purple here and there… a bit more couldn't hurt, buying a few new pillows and blankets didn't mean he was nesting… it just meant he wanted to change his personal space up a bit, brighten it up a little.
"Purples… I have mostly darker shades in my bed now, maybe I could do with some lighter shades?" he offered as they reached the bedding and nesting section.
- - -
For the first time since presenting, Mori built a nest.
There was no other way to describe the space he had created, even going so far as to retrieve his comfort items that usually, he only pulled out while in heat.
The first, an old haori he'd claimed from Yukichi while they had been partners, when the older man had made him feel safe and content, now a bittersweet reminder that the one Alpha he'd thought could love him as he was, saw him as nothing but a monster.
The second was a large plush bear, he'd originally purchased for Elise, but after he'd come to live with them, Dazai had claimed it as his own, sleeping on it and wrapping his old bandages around its limbs, the boy's smell imbedded into the artificial fur. Mori didn't know what it was about the bear that brought him comfort, but it did.
He assumed it reminded him of the initial couple of months after he'd found the boy, Dazai couldn't seem to sleep alone, and often crawled into Mori's bed with him, wrapping himself around him like a leach.
Mori himself could not deny he slept better with Dazai by his side, their scents mixing together, lulling him into a comfortable slumber.
"Since when do you nest?"
Speak of the devil and he shall appear, Mori turned to the entrance to his bedroom, where Dazai stood.
"I don't." Mori said, glancing back at his bed from the corner of his eye, just because he'd finally decided to give in and build a nest did not mean he had developed a nesting instinct.
Dazai laughed, closing and locking the door behind himself as he came further into the room, "That looks like a nest to me, Mori… why the sudden change?" He asked, sitting to the side of the neatly organized wall of pillows that bordered the nest.
Shrugging, Mori sat beside the boy, unsure of how to respond. He couldn't even make an educated guess… his only thought was that possibly Dazai's presentation had triggered the instinct, having an overprotective and possessive Alpha in such close proximity all the time– but then again, he'd never nested for Yukichi…
Taking hold of the old haori, Mori wondered if he had truly felt safe with him… trusting him with his life wasn't the same as feeling safe and protected.
Mori was pulled from his thoughts when Dazai ripped the clothing item from his hand and tossed it to the floor before practically tackling him into the nest, burying his face in Mori's neck and beginning to scent him. "Mine!" He muttered into his skin.
Smiling, Mori laid there and allowed him to do as he pleased, "You're not going into heat early, are you?" Dazai eventually asked after some time had passed.
"No, Dazai. I'm not going into heat early. That's still over a month away." He replied, rolling his eyes even though they couldn't be seen.
Pressing his nose deeper into the gland on his neck, Dazai breathed his scent in, "Then why?" He asked, tone curious.
The Omega had noticed that since presenting a few months ago, Dazai had become far more possessive of him.
Dazai had always been possessive, from the moment he'd taken the boy in, but presenting as an Alpha had only increased that instinct.
Mori found it to be adorable–annoying at times, but adorable nonetheless.
Far more comfortable than he expected to be in such a position, Mori relaxed, slowly raising his hand to begin running it through Dazai's hair while he worked to cover him in his scent. "I don't know… I just felt like it. Do I need another reason?"
Dazai mumbled a soft, barely audible 'no' into his neck before going back to scenting both Mori and the nest.
- - -
Only a few days after Mori had built his very first nest, Dazai had his first proper rut.
It had come completely out of nowhere, neither were prepared for the next few days of hell the poor boy had to suffer through.
Mori was just glad that Dazai's Alpha fangs hadn't fully descended yet, with the amount of time the boy spent trying to bite him.
For the most part, Dazai had spent those three days withering in pain, crying for Mori to hold him and bath him in his scent, something the older Omega was more than happy to do, but every so often, Dazai's instincts would take over and he would attempt to pin Mori down and mark him. The worst he'd been able to do was leave a couple of scrapes and bruises around his mating glands.
Now, a few days later, it was over and he spent most of his time napping, allowing his body to recover from his rut.
His favorite place to nap being Mori's lap, wrapped securely around the omega, so that it was near impossible to move him to a chair or bed once he was asleep.
Both Hirotsu and Kouyou had witnessed him attempt to fight off the little leach earlier that day before a meeting, only to watch the head of the Port Mafia give up and just carry the boy into the meeting with him, allowing the baby Alpha to cling and drool all over him while they discussed the fate of the city.
- - -
It wasn't unusual for Mori to dred an oncoming heat cycle, they were exhausting and painful, leaving him weak and vulnerable to attacks from his many enemies.
His newest reason was sitting in their nest, arms crossed and pouting. "I still don't understand why I can't stay. You stayed with me when I had my rut! What's the difference!?"
"As I've already explained to you Dazai, it's not safe." Mori said for what felt like the millionth time that evening.
Dazai continued to sit there, pouting and angry, Mori let out a defeated sigh before joining him in his nest, pulling the boy into his lap while making himself comfortable among the pillows. "Look at me, Dazai." The boy just shook his head, burying it into Mori's chest.
Deciding to let him calm down before speaking again, he began running his fingers through his hair, offering up a few soft purrs here and there to try and calm him further.
Eventually Dazai made a sniffling sound and squeezed his arms around the Omega's waist, "I don't want you to be alone…"
Pressing a kiss into the crown of Dazai's head, Mori pulled him closer with his free arm, "Oh my little Hellspawn… I'm not sending you away entirely, it's only a few days, I'll be fine–I have Elise to look after me and keep me company, so I won't be completely alone."
"It's not the same."
"I know… but it's for the best, you don't want to hurt me by accident, and I don't want to do anything that could cause you harm. It's just safer for now that you keep your distance while I'm in heat."
Dazai readjusted himself so that his face was buried in Mori's neck rather than his chest, "I still don't have to like it." He said before he began licking and nibbling softly at his mating gland, not breaking the skin, but imbedding his own scent into the skin there.
Allowing Dazai to do as he pleased, Mori began purring more loudly, he had no more words, only the comfort he hoped the sound evoked.
- - -
When Mori's heat finally came, it was unpleasant for both of them.
Not only suffering the usual aches, pains, hunger and that usually accompanied his heat, Mori also felt as if he was suffering a withdrawal.
Having spent so much time with the young Alpha so close, he'd grown accustomed to his proximity, the scent he left within his nest only doing so much to satiate him.
Currently, Mori was huddled up against his bedroom door, having dragged most of his nest to the floor to be as close to Dazai as was possible at that time, the boy spent every free moment he had sat against the door, growling at anyone who dared come near.
In his few lucid moments, Mori couldn't help but be amused by how protective and territorial Dazai was already, he wondered how much stronger those instincts would grow as Dazai matured.
How they would evolve once Dazai was able to give him a proper bonding mark–rather than the marks that were basically just hickies he was currently leaving along his mating gland at every opportunity.
When his lucidity would fade, he did his best to focus on Dazai's scent, letting it ground him in reality, as much as anything could when he was in this state.
He liked listening to Dazai talk, too. Though he could rarely understand him, between the door and the heat cloud he was buried under, just hearing the sound of his voice was enough to bring him some modecome of peace.
The Alpha's voice distracted him from the burning agoning shooting through his body, Mori couldn't help but be glad Dazai never listened to him at that moment.
Eventually his words tapered off, and Mori heard the sounds of shuffling on the other side of the door before noticing a couple of fingers poke out from under the door, followed by a sound that took far too long for Mori to recognise.
Dazai was crooning.
Mori had never heard the boy make such a sound before, going by how small and creaky it was coming out, it wouldn't surprise him if this was his first time doing so.
Touched by Dazai's persistence in his desire to keep him company, Mori reached one hand out from his cocoon of blankets, resting his own fingers over the once Dazai had squeezed through the gap between the door and carpet, returning the gesture, he offered up his own weak purrs.
Feeling as close to peace as he had ever felt in another's presence.
Mori never believed he would find an Alpha that could match him, though he would be alone forever.
For the first time in his life, he was glad to have been proven wrong.