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While Giyu knew Master Kagaya had sent Tanjiro to his estate to try and convince him to participate in the training of the demon slayers, It didn’t stop him from being incredibly uninterested in the omega’s persistence. He wanted to be left alone was that such a hard concept to understand? He didn’t deserve to be the water hashira, that title should’ve gone to Sabito. Not him. But no one seemed to get that. Especially not Tanjiro who’d been relentlessly following him all the time, he couldn’t even take a bath without the kid randomly appearing in his window! It was ludicrous.
Giyu took a step out of his room, it was early in the morning and he was still in his sleeping kimono because he was going to try and make himself a cup of tea before Tanjiro woke up and started trying to convince him to let every demon slayer in the core come to his estate to train, The other hashira would be better suited since they were actual hashira and not a false hashira like him. He carefully avoided the creaky floorboard of the engawa as he glanced down towards a sleeping Tanjiro who’d decided the best place to sleep was right outside his door, it made his stupid alpha brain was sad that his pup- wait what? Since when did he think of Tanjiro as a pup? Let alone his? He shook the thoughts away, His stupid alpha brain was sad because Tanjiro was sleeping on the hard floor instead of a comfy nest or something-
His nose twitched as a scent caught his nose, there was Tanjiro’s usual scent of charcoal and smoked wood, which he was used to since well he’d been around this kid for a long time. But there was also something faintly sweet- Oh gods above had the brat (why was he calling his- shut up brain Tanjiro is not his pup- a brat?) gone into heat while he was here? Great exactly what he needed. It wasn’t his problem, His sister had been an omega so the scent of heat didn’t bother him at all so why was he worried? This wasn’t his problem, maybe his brain was only acting up because some of the kakushi around his estate were alphas, yeah that could be it. But they should know better than to mess with an omega- let alone an omega in heat. And yet something urged him to wake Tanjiro up, something protective and paternal wanted to dote on him which was utterly stupid and downright weird because Giyu isn’t related to him at all and it could be seen as inappropriate-
And yet he still found himself nudging Tanjiro awake. He stepped forward hesitantly as he crouched a bit. He was a bit reluctant to wake the other up because of the possible outcome but he needed to make sure Tanjiro was okay so he carefully nudged the other “Hey, kid wake up” he said in what he hoped was a stern voice, but to his surprise, it came out a lot more worried than he had hoped. He frowned as Tanjiro let out a small whine, that was definitely a sign the brat was in heat. Great.
Tanjiro whined as he blinked awake, He looked over at Giyu not yet realizing that he was in heat yet as he smiled brightly, “Mr. Giyu!” He said cheerfully “Good morning! Are you ready to start training?” He asked curiously as he sat upright instead of lying down on the wooden engawa.
Tanjiro was very persistent on his task of getting Giyu to start training the other demon slayers, it was tasked to him by none other than Master Kagaya himself! So he had to do his job! And make the sickly man proud! Right?
Giyu blinked at the other's enthusiastic personality, the way he talked one would think he wasn’t in heat at all. He should probably remind him of that though it seemed like the omega in front of him hadn’t even realized himself. He sighed softly before finally muttering the dreaded sentence. “Tanjiro- you’re in heat… you should go back to the butterfly mansion” he muttered. He really hoped that the other omega would just agree, he really didn’t want others in the comfort of his estate.
“Huh? I am?” Tanjiro asked as he took a second to actually sniff the air, he blinked as he realized that in fact, he was in heat. “Oh.” He said with a frown before laughing, “I guess I didn’t realize!” He said cheerfully as he got up to stand up to face Giyu. “But I can’t leave until you agree to train the demon slayers!” He said stubbornly.
Giyu stared in shock at the kid in front of him, there was no way he heard that correctly. He had to be messing with him! Right? He couldn’t be serious, there was no way even Tanjiro was that stubborn to put himself in danger for a task, was there? He looked at the other with an incredulous expression “Tanjiro you can't be serious, You need to go back to the butterfly mansion. You are in no state to stand here and demand I train others, that can wait. Your first priority should be the safety of your health.” He argued.
“But Master Kagaya gave me a task! I can’t just not do it!” He argued back as he crossed his arms stubbornly, ignoring the faint pain around his stomach as he winced ever so slightly.
His heats always kinda sucked, He always cramped and bled a little bit and he always had a migraine during it but that was fine! He had a job he needed to do some stupid heat wouldn’t stop him.
He watched as the omega winced in pain slightly and frowned. He knew Tanjiro got bad heats, Nezuko used to get bad ones too and she’d always need a nest, and someone to comfort her- at least that’s what Urokodaki said. But that made him curious, did Tanjiro have a nest? Did he have someone to comfort him like his sister had? Maybe that was why the other didn’t want to go to the butterfly mansion. It wasn’t uncommon for omega’s to get uncomfortable with strangers during heats. He paused before finally sighing and muttering something under his breath.
Giyu stepped towards the omega in front of him and grabbed his arm gently, he knew how Tanjiro’s heats were and he knew how hard it could be to deal with. He wasn’t particularly the best at comforting others but he’d try his best. He was an Alpha Tanjiro was familar with so perhaps that would help? “Tanjiro come with me,” He said quietly and carefully pulled him towards his bedroom before letting go of his arm once they were there. “Stay here until your heat is over,” he said quietly, he hoped the brat didn’t protest, Something paternal in his in Giyu’s opinion very dumb alpha brain insisted the omegan pup should be somewhere safe and cozy where no one unruly or with disgusting intentions for the sweet omega pup who was basically a ray of sunshine.
Tanjiro hesitated, he was supposed to be persistent in getting Giyu to train the demon slayers, he was supposed to stop Giyu from isolating himself, supposed to make him a proper member of the demon slayer core
And yet the idea of curling up in Giyu’s bed was more than tempting, His stupid heat brain wanted nothing more than to cuddle and nap in a nest and maybe even scent Giyu-
He shook his head. “I can’t accept that offer Mr. Giyu!” He said politely.
Giyu sighed before he finally grabbed the other by the front of his haori and dragged him into the master bedroom, the omega obviously wasn’t seeing how much of a bad idea it was for him to be insisting on something so stupid.
He was a bit frustrated that the omega was being just as stubborn as he was, if not even more stubborn! He gently set Tanjiro down and spoke in a firm tone. “Lay down Tanjiro, you’re not going to convince me to do anything right now, and with how persistent you are while in heat you're going to push yourself too far.”
Tanjiro blinked before sitting up. “But Master Kagaya insisted!” He protested with a hint of whine to his voice as he looked at Giyu with narrowed eyes and puffed-up cheeks. “I’m supposed to be helping you! I can’t help you if I’m kept in your room all day!” He argued with a pout.
Giyu couldn’t help but find the other's pout adorable. He shook his head at the other as he finally responded with a soft sigh. “Tanjiro you can tell the master you’ve convinced me when you’re not in heat-“ He said and then paused as he realized what he was saying. He just told Tanjiro he would agree to training the others after his heat. But why? Why did he just say that!? He shook the thoughts away before finally speaking again.
“Now lay down before you faint,” He said sternly as he lightly pushed the brat down into a laying position.
Tanjiro smiled brightly, his dark red eyes twinkling excitedly as a purr threatened to build up in his chest as a feeling of pride as he realized he’d completed his task he had been assigned! He’d done it! He’d done what Master Kagaya had instructed him to do!
He couldn’t help as a happy sweet purr rumbled out of his chest as he let Giyu push him down on the bed, still smiling brightly because he was proud of himself for convincing the cold and distant hashira to train the other demon slayers!
Giyu couldn’t help but feel his own inner alpha melt a bit as he heard the others purr. His inner alpha always did this, he didn’t know why but whenever he heard an omega purr it made him want to give them his full attention and to comfort them. He pushed away the thoughts and carefully pulled the blanket over the omega “There now get some rest.” He said softly and went to walk away. After all, it wouldn’t benefit the other if he just stayed in the room. He didn’t know how to comfort omega’s anyway.
Tanjiro suddenly whined as Giyu left, moving to sit up, “Don’t goooo..” Tanjiro whined his pupils dilated as he reached out for Giyu, his stupid omega brain already getting all fuzzy and instinctive now that his goal had been achieved, he didn’t want Giyu to leave! If Giyu left then he would be left alone and unprotected!
Giyu paused at the whine and the small plead of ‘don’t go’ This wasn’t a good idea but his omega instincts were screaming at him to stay, and well to his own surprise his alpha side was agreeing, it felt weird. Sure his instincts made him protect omega’s, but he never craved the scent of another so much. He sighed softly before turning around and walking back to the bed “Alright I’ll stay” he mumbled softly as he moved to sit on the edge of the bed.
He glanced over the omega before scooting closer to him as he carefully wrapped an arm around the other's shoulders and pulled him closer. He felt his instincts urging him to hug the brat but, he didn’t know if Tanjiro would agree and just because his instincts thought it was a good idea didn’t mean it was. He was sure if he tried to hug the other, the brat would push him away and say something embarrassing. “Is this okay?” He asked hesitantly.
Sure he was doing this for the pup’s sake but he didn’t want to just do what he wanted-
Tanjiro purred sweetly as he laid down against Giyu, sprawling across the alpha’s lap as he rested his arms on Giyu’s knee before laying his head down as he yawned sleepily, stretching out to lay across Giyu and the bed as he purred like some blissed out sun drunk cat.
He blinked in surprise when the omega sprawled out on his lap, he’d thought the kid would reject him not lay down in his lap like a pup! He was at a loss for words as he watched the kid get comfortable, gods the other was adorable. He found himself softly rubbing the other's back and subconsciously purring along with the young omega. He quickly stopped though when he realized he was purring. He didn’t want to weird the poor kid out, after all, he was the omega’s superior in both rank and age.
He glanced down as he realized the omega’s eyes were fluttering slowly, he was definitely tired. He looked around the room as his hand absentmindedly played with the other's hair. He found himself doing that a lot, he didn’t know why. But oh well, he let his fingers gently run through the other's hair as he tried to think of what to do now. He had a feeling the kid would want him to stay but it’s not like he could just stay in the room the whole day-
But what else was there to do? If he left the idiot brat alone he’d probably do something dumb like wonder off
Tanjiro purred pressing up against Giyu’s slender pale fingers, his chest basically vibrating from how much the little pup was purring in contentment. His scent becoming sweeter from his happiness and contentment
Giyu found it a bit endearing how easy the other was to please, not that it was really surprising since well he was an Omega. He thought back to when he was comforting Sabito, he’d always liked it when Giyu had played with his hair and purred against him. Was that how Tanjiro felt right now? Did the pup also feel calm being comforted with simple little gestures. He couldn’t help but smile softly as he watched the omega slowly drift away into a blissful sleep. He sighed a bit, maybe he could also take a nap while he had nothing else to do.
He shifted a bit before carefully laying back against the headboard of his bed and letting his own eyes shut as he thought more about the sleeping pup resting in his lap. His fingers absentmindedly played with the other's hair as he sighed softly. It felt nice to have someone to comfort again after so long, after he had lost Sabito he had never let himself get close to another omega, he’d lost so much that he didn’t want to be weak again like he had been when Sabito died. He couldn’t go through that again, it was painful.
He didn’t know when or how but eventually he also found himself drifting away into a relaxed sleep. He hadn’t slept this well in months, it was comforting to have someone to care for. It might seem odd to outsiders because of who he was in the corps, but he loved caring for those he had let into his heart. Tanjiro had done it, the young omega had done so without realizing it. Not that he minded, well he didn’t think he minded anyway. Maybe he felt like this because he was an alpha and Tanjiro was an omega, it was natural for an alpha to have instincts to protect and provide for a lone omega pup.
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Giyu had been sleeping peacefully but the feeling of something shifting in his lap woke him up abruptly. He groaned softly as he forced himself to open his eyes. He looked down and blinked as he saw that Tanjiro was missing from where he had fallen asleep. He was tempted to sigh but his alpha instincts urged him to find the young omega. He carefully got out of his nest and opened the door. He looked around for the younger omega before the scent of heat caught his nose, he slowly followed his nose before stopping in front of the bathroom door, the smell of vomit and distress wafting from the room as he knocked on the door, “Tanjiro?” he asked quietly.
Tanjiro whined pitifully as he vomited once again, the vile acid burning his throat as it came up, He whined again as he dry heaved, clutching the cold porcelain under his calloused hands as he gagged before throwing up pure stomach acid, his teeth tingled uncomfortably as he blearily looked over at the door. “Mr. Giyu.?” He croaked in the most pitiful broken voice Giyu had ever heard him use as the bitter scent of a distressed omega wafted through the door.
He couldn't help the small whine that escaped him as he smelled the other's sweet pheromones mixed with the overwhelming scent of distressed omega. He could also smell blood which caused his instincts to go crazy. He knew what was causing the blood, every omega had to deal with it. It was a painful time and he only wanted to help the struggling omega.
He carefully pushed open the door and stepped inside quietly, he walked over so he was standing behind the younger. He knew the omega likely felt disgusting right now but it was a natural thing and he would help them both. "Tanjiro..." He said softly as he reached forward to run his hand up and down Tanjiro’s back.
Tanjiro threw up again, his stomach was empty and he was only vomiting out stomach acid, he whined as Giyu came over, wanting nothing more than to bury himself in the alpha’s arms.
And so when he was completely sure he was done vomiting it was exactly what he did, he buried his head in Giyu’s shoulder as he whined practically begging for comfort as he clung to Giyu like his life depended on it.
He felt his heart shatter at the feeling of the omega clinging to him. It hurt to hear such pitiful small noises coming from an omega in so much pain, that he carefully scooped the younger up in his arms and carried him back to his nest. He set down the omega before leaving the room so the omega could change his clothes into a comfy pair of sweatpants and a tee shirt from Giyu’s clothing.
He grabbed a thermometer to check the omega's temperature and was surprised he already had a low-grade fever. He carefully put the thermometer back and climbed into his nest and pulled the omega against him.
Tanjiro whined pitifully, his scent glands hurrrrtttttt and his brain was all weird and fuzzy and foggy and he didn’t like it and he was all whiney and achy and he wanted to know why Omegas had to go through this because it was so freaking annoyinggggggg
Tanjiro buried his nose into Giyu’s neck, quietly scenting the alpha as his pitiful whining turned into a little half-hearted purr.
He felt a lot calmer once the younger started purring, it meant the omega was beginning to relax. He wrapped both arms around Tanjiro and began releasing calming pheromones of his own to soothe the younger. Once Tanjiro had stopped making the distressed noises he glanced down at the omega in his arms.
Sure he was an alpha who was supposed to be all tough and strong but the truth was that he loved to dote and fuss over those he let into his life. He couldn't help it, especially since the only one he had cared for so deeply after Sabito was his older sister.
He pulled the omega impossibly closer as he thought about how they got to where they were now. It might’ve just been instincts but he couldn’t deny that the omega had grown on him. He wasn’t an idiot. He was a hashira for god's sake but when it came to emotions he was clueless, sure he knew what they were but when it came to expressing them himself he got awkward. He was used to the angry and depressed side of himself. Not this new caring person he was turning into, but he couldn’t help but like it.
But he was getting off-topic for now he just needed to focus on comforting the omega on his arms, whose small whines were starting to become more frequent. He sighed and looked down at the younger, he wondered if the pup knew how cute his small mannerisms were. He doubted it, if the brat even knew that he was currently clinging to him for dear life he probably would’ve tried to protest it.
He looked around when his eyes landed on a brush. Oh, what the heck he’d already done other weird things why not do this too? He carefully grabbed the brush and slowly ran the brush through the omega’s hair.
Tanjiro purred happily as Giyu ran the brush through his red and black hair, he actually was purring quite loudly as he snuggled closer to the water hashira, he was more than happy to get the affection and attention that his stupid omega brain so desperately wanted- or well no, needed is a better word
He found himself relaxing the longer he worked the knots out of the omega’s hair and listening to the way his purring got louder when he got the brush through a stubborn tangle. The sound was a comforting one that told him he was doing a good job at comforting the younger. He gently set the brush down at his side once he was done.
He looked down at the pup in awe, he had no idea omega’s were this affectionate. He knew they craved affection but this? This wasn’t anything he had seen before, he loved the affections of course but it was odd.
He couldn’t help the fond smile that spread across his face as the younger looked up at him. He carefully reached out to run his fingers through the omega’s hair. The pup was already in his arms, why not just give in and be the big spoon? It wasn’t like he hadn’t already doted on the pup today. Sure it made him weak to give in but if it meant the omega was comfortable and happy he didn’t care.
As soon as he was in position he felt the omega practically melt into him. He couldn’t help but chuckle a bit. The small pup seemed to thrive off the affection he got. Gods he was weak for this little omega, he’d deny it when they asked, but being around him brought him so much happiness. The poor pup was so clingy but at this point, he couldn’t bring himself to mind the younger’s clinginess, if anything he found it adorable.
Tanjiro smiled brightly as he was cuddled against Giyu, his eyes basically twinkling and sparkling from how much he was enjoying the comfort and warmth and doting attention from the water hashira.
He bit back a pitiful whiney huff as he scratched at his scent gland with his blunt nails, it was swollen and hurting, and honestly scratching at it didn’t really help and kinda hurt-
Giyu found his heart melting as he watched the pup act how any omega should when being given affection
He couldn’t help but frown when the younger one scratched at his scent gland. He had a feeling he knew how to help, but he wasn't too sure. He knew omega’s usually wanted their scent glands rubbed after a heat but what would happen if the pup’s scent gland was swollen and hurting? Would anything bad happen? He didn’t know but he couldn’t just sit and watch the omega suffer. He carefully moved his hand and gently gripped Tanjiro’s wrist.
"Don't scratch at it Tanjiro. You'll make it worse." He said as he gently pulled the pup away from the inflamed scent gland. He wasn't sure what he was doing but something was urging him to do what he had planned. He slowly let go of the omega and moved his hand to gently rub and press down onto the omega's scent gland. He had no idea what the outcome was going to be, but he couldn't just ignore the omega's pain. It wasn't in his nature to just watch someone he cared for get hurt.
“But it hurtssss,” Tanjiro whined as he squirmed in Giyu’s hold. He wanted it to stop hurting! He wanted it to stoppppppppp! It’s all red and swollen and hurting and it made him want to scratch at it-
And oh that feels good, he purred loudly as Giyu pressed down and rubbed at his scent gland he snuggled closer to Giyu letting out content little blissful chirp noises.
Giyu couldn't help but melt the moment the omega started purring when he massaged and gently rubbed at the swollen scent gland. He was so glad the pup wasn't in pain anymore, he also purred with Tanjiro as he moved closer to the other. His instincts were going absolutely wild now, the urge to scent the omega was overwhelming him. Of course, he'd be lying if he said his alpha hadn't been screaming at him the entire time to mark the pup as his.
Scent marking was completely different than marking a mate (not that he’d EVER thought of doing that to Tanjiro, he was a pup and Giyu was a lot of things but one thing he isn’t is a pedophile.)
Scent marking was a way of telling the entire world to ‘stay away! this person means a lot to me and I am willing to fight to protect them!’ And he so badly wanted to scent mark the sweet little ray of sunshine in his arms but doing so without explicit permission was a massive no in Giyu’s mind.
He knew he needed to ask the omega for permission. “Tanjiro,” He said hesitantly. He couldn't just do it without asking, he wasn't a complete and total dunce when it came to omega dynamics. He knew the risks if he did go through with this. He was just worried if the omega would trust him enough to scent them. Sure he had already done many things to soothe and help the omega but scenting was different. He sighed softly “Can I scent mark you?” He asked quietly, he was scared of the possible rejection but he knew it wouldn't be the end of the world.
Tanjiro looked up at Giyu with a big bright smile, If he had a tail it would be wagging enthusiastically as he nodded immediately. “Yes! You can!” He said excitedly, Scent marking was a very personal and very affectionate gesture, And Tanjiro would be absolutely honored if Giyu wanted to scent mark him! That was like- the sweetest coolest thing ever!
Giyu was a bit surprised the omega had agreed so quickly. Of course, he wasn't complaining, but it was a surprise nonetheless. He slowly brought his wrist up to the omega's scent gland and started rubbing it slowly against the scent gland.
He purred softly as he saw the omega lean into his touch. He was a bit confused about why he wasn't feeling that nervous but then he remembered that Tanjiro was actually just a very comforting person to be around so it wasn't that surprising.
Tanjiro closed his eyes as he purred happily, his scent changing to a happy pure childish scent of charcoal and oddly enough spider lilies as he stretched out before cuddling against Giyu, looking up at him with happy nearly black eyes before he shut them again, content to fall asleep like this
Giyu felt his heart melt as the omega purred and looked up at him with such innocent sweet little eyes. He smiled softly at the other as he gently wrapped his arms around the younger and hugged him. He started releasing his own calming pheromones to try and help the other fall asleep. He was happy that the omega wasn't in any more pain, he knew it was all thanks to himself but it still made him happy to be needed. He gently stroked the omega's back as he watched him fall asleep, he wouldn't be surprised if a loud purring lulled him asleep too.
He stayed like this until eventually, the omega's soft purrs turned into more snores from the younger. He carefully pulled the blanket over the both of them before slowly letting himself drift to sleep. He would take care of Tanjiro while he was in heat, he'd do everything in his power to keep the younger safe, especially since his instincts were so loud when it came to protecting an omega. He wouldn't even dare leave the pup’s side during this time.