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Stellarum Geminae

Chapter Text

“I fuckin’ hate snow.”


Izuku Midoriya couldn’t hold back a fond chuckle at the blonde man next to him quietly grumbling. He anticipated the growl and rib jab in retaliation, moving out of the way just as Katsuki’s hand flew by. This time he laughed properly, the bright smile on his face so large that he was sure his face would start hurting soon enough.


The woodlands in the winter were beautiful. The tall beech trees nearly glowed in the sunlight as the sun sank in the sky to usher in a brutally cold winter night, the snow laden branches glittering like crystals. The oak trees, once part of a lush canopy of greenery, were stripped bare of their leaves. The dark bark contrasted beautifully with the untouched white snow piled on each branch. Izuku sighed in contentment. He’d always felt more at home out in the wilds, more so than any other person he’d met. Except the blonde man he’d followed into the woods perhaps.


Katsuki Bakugou. Son of the current chieftains of the elusive Dragon Clan, Masaru and Mitsuki Bakugou. The very definition of wild in Izuku’s mind, Katsuki had come to mean safety and adventure, even if the bad tempered Alpha acted like Izuku was more of a hindrance than an asset.


Katsuki was taller than Izuku by nearly half a head when he was in his human form, with wild blonde hair that stuck up in spikes and piercing red eyes that scared many a lesser man. Red fangs hung from holes in each ear and matched the flowing red cloak Katsuki wore as a symbol of his rank within his clan. A thick spray of fur wrapped around Katsuki’s shoulders, clearly intended to keep the wearer warm during seasons such as this. Katsuki wore a plain gray long sleeved vest that barely reached the end of his impressive pecs and hung open despite the winter’s chill. White fur lined the waist of his dark gray trousers, a plain leather belt with two curved short swords and their scabbards attached settled atop the fur and held the ensemble together. Heavy winter boots dyed gray to match his vest kept his feet warm.


Izuku couldn’t imagine having any part of him exposed to the frosty air. He was in a white long sleeved tunic with his customary green vest buttoned over it, thick leather gloves on his hands and his own green cloak clasped at his throat. His trousers were dark blue and his signature red winter boots adorned his feet. His own sword and scabbard were a comforting weight against his back, the leather cross strap tightly secured against his chest.


“You done daydreamin’ yet, asshole?”


Izuku started, his green eyes snapping to Katsuki while a blush crept across his cheeks at being caught. He took a deep breath to center himself and breathed in Katsuki’s scent. The smell of campfire smoke and burnt sugar invaded his senses, the Omega in him practically salivating at the scent. Katsuki smelled like everything Izuku wanted in life. Too bad Katsuki didn’t see it the same way.


The Alpha had only a begrudging respect for the green haired Omega, nothing more. He’d stumbled across Izuku fighting a one eyed giant purely by accident one day almost six months ago. Before the blonde could leap in to kill the giant and save the useless human, Izuku had managed to kill the giant by himself. It didn’t stop Katsuki from berating Izuku for fighting a fully grown giant alone or criticizing his sword technique during the fight, however it did force him to admit that the Omega could be worth a damn if he was taught correctly. Izuku had laughed and asked the blonde if he intended to be his teacher.


And here they were, six months later, trudging through the knee high snow to continue combat training.


“Yes, Kacchan!”


Katsuki rolled his eyes at the stupid nickname the Omega had given him. It was all just for show, though. Katsuki was secretly touched that he’d been given the nickname from such a pure person like Izuku. He’d never admit that fact to anyone, nor would he ever divulge the real reason he’d offered to teach Deku.


The Alpha had known the second he’d laid crimson eyes on the green haired Omega that Izuku was his . His instincts had screamed for him to save the human before anything could happen, startling the fuck out of Katsuki because he’d never given a damn about anyone but himself and his clansmen. He was caught off guard by such an intense reaction to a literal stranger and had hesitated for a long moment to focus his mind back on the battle. Only to find that the shorter man had killed his opponent without his help whatsoever. He’d scrambled to figure out a way to keep Izuku around and settled on offering to teach him better sword efficiency.


The slide of steel as Izuku drew his sword snapped Katsuki out of his nostalgia and he let his face fall into the same cocky smirk he always wore going into battle. They’d finally arrived at the small clearing deep within the woods they had been using to train, away from prying eyes and safely tucked away to where they couldn’t harm anyone if they went all out. He drew his own curved short swords and continued to move several paces away before stopping to turn and face Izuku.


“What’re we working on today, Kacchan?”


Bright green eyes looked at Katsuki like he was the most important thing in the world. He swallowed against the emotion that threatened. He didn’t want to be the most important person in the world, he just wanted to be the most important person in Izuku’s world. Soon he’d have to figure out how to reveal his feelings for the other man. But for now he placed everything to the side so that he could focus solely on the fight between them.


“Today we’ll be focusing magic into our sword attacks and using it to boost our sword strikes. You ready?”


Izuku sunk into his battle stance, a confident smile that caused Katsuki’s heart to skip a beat turning his lips upwards. His green eyes were intense as he focused on Katsuki. A wind began to blow, swirling around Izuku and flinging snow into the air with its force. Izuku remained still, his green haired curls whipping around wildly and his cloak being buffeted straight upwards. Izuku closed his eyes and Katsuki could see him take a deep breath before green lightning began sparking in the maelstrom.


Katsuki would never grow tired of watching Izuku summon his godlike power. The hairs on the nape of his neck stood straight up with the sheer amount of static electricity in their small clearing. He wasn’t worried about getting shocked, knowing that Izuku was in full control of his magic and having his own special defenses being Dragonkin, he could withstand the lightning storm in front of him in order to appreciate its beauty.


The lightning closed in around Izuku, flashing so rapidly that Katsuki could only see glimpses of the Omega, the wind merging with lightning to create a brilliant tornado. He heard Izuku shout and barely saw him raise his sword towards the sky before a flash of light so bright it forced Katsuki’s eyes closed against his will shone through the clearing.


When Katsuki cracked his eyes open, black spots still danced in his vision and obscured the world around him. He blinked rapidly several times to dispel the spots. Once his vision returned to normal, he was able to take in the man across the clearing.


Izuku still had his sword raised to the sky. Wind no longer stirred around him and his clothes were composed once more. The blade of his sword cackled with the green lightning that had just charged the air. Izuku moved back into his battle stance after another moment of silence.


“I’ve been ready to get to this point for a long time, Kacchan! I can’t wait to see how I do against you. Even if I only last a moment, it’ll still be the greatest accomplishment of my life.”


Katsuki fought the blush that threatened to stain his face pink at the Omega’s words. Izuku had no idea how his words could be read, so dense even for a nerd that Katsuki doubted the shorter man would understand if he attempted to point out their double meaning.


“You’re fuckin’ embarrassing, is what you are. You better last longer than that, otherwise I’ll be insulted that my teaching wasn’t good enough to teach a nerd like you to fight properly.”


Katsuki’s smirk turned bloodthirsty as he watched Izuku sputter. It amused him to no end that Izuku could be so deadly serious one moment, an opponent to be feared, and in the next heartbeat could turn into a stuttering nerd.


“My turn.”


Izuku’s noises cut off at Katsuki’s words. Katsuki crossed his own swords in front of him, his posture relaxed and confident as he closed his eyes. His emptied his mind, used to the routine needed to call upon his dragonfire for use in his human form. He mentally reached out towards the fire that burned at his core, his own unique warmth that could help or scorch depending on how he intended to use it. His pride for his heritage gave the fire strength, and his heart gave it purpose.


Izuku held his breath without realizing it. Katsuki’s fiery magic was amazing, and he’d always felt such pride for Katsuki and his ability to protect and defend what he held dear. He thought of his own mother and his reason for leaving their village; to find out where he fit in this world, what his purpose was. He didn’t know it at the time, but he was searching for the strength that Katsuki wielded so effortlessly.


Fire flared to life around Katsuki. Flames licked at his skin, popping and crackling like mini explosions against his clothes. Crimson eyes snapped open and Izuku could see the fire reflected in their depths, down to Katsuki’s very soul. It was a beautiful sight every time he witnessed it, this time was no exception. Izuku felt the brand of those fiery eyes sear his soul, melting him down only to build him back up again.


Katsuki’s blades turned red as the magic channeled through them, mini explosions still crackling around them. He lowered them slowly, well aware of the green gaze upon him. The Alpha in him revelled in the strength coursing through his body, intent on showing this Omega how powerful he was, how much he could protect him for the rest of their lives. A low growl slipped out of Katsuki’s throat.


“Whoever loses cooks dinner.”


Katsuki set the reward for winning as he always did. The reward differed each time; sometimes it was a favor, a conversation, an item, a chance to do something together. He found that Izuku fought harder, harder and better , if he had something to fight for . No matter how menial or small that something might be, Izuku fought for it as though it was special. Izuku would be a real threat to whoever threatens something he holds dear, if he fought with everything he had for a stupid reward between companions.




Katsuki moved in the next instant, his swords in position and his face set in concentration. At one point Katsuki’s speed and ferocity scared the shit out of Izuku. But after all the time they’d spent together, he knew that intensity was just part of who Katsuki was . He brought his sword up to block the blades, lightning and fire mixing and exploding as they clashed.


Katsuki threw his blade up to block Izuku’s incoming swing at his ribcage, his other blade sweeping towards Izuku’s leg. He laughed as Izuku stumbled away just before his blade kissed the fabric covering his skin. Here, wrapped up in the fight between the two of them, he felt the world fall away. There was nothing but them; nothing but the fight raging, the sense of rightness that settled over him any time Izuku was near, the scent of the green haired Omega in his lungs.


Izuku smirked at Katsuki’s laugh. He knew the fiery man wasn’t laughing at him. Katsuki had always been more at home on the battlefield. He was sure of his strength, sure of victory no matter the cost. It was what attracted Izuku to him in the first place. Now, he hoped to prove to the Alpha that he was worthy to be his mate. If he could just best Katsuki in a fight, he’d tell the man how he felt.


Their swords crossed again and again, the sharp sound of crashing steel and explosive magic like a symphony around them. Izuku was starting to feel the drain on his body as he worked to keep his magic fortified in the blade. He was so close to winning, Katsuki fighting all out now that an easy victory wasn’t possible. His mind raced to come up with something to give him the edge, the final push to drive Katsuki away and attack.


Katsuki focused on the tells Izuku broadcast, small twitches and moves that told Katsuki how tired the man was. If he could find an opening in Izuku’s defenses he could end this fight. But even though Izuku only had one sword, it felt as though that sword was everywhere. No matter how many of Katsuki’s sword combos he utilized, that sword was always there at the last moment, protecting its wielder and deflecting his attacks. Katsuki’s swords were an extension of himself, he’d been training with them since boyhood. He felt the flow of their power throughout his body. In that power he found the reassurance that he could win this fight.


Izuku watched as the look in Katsuki’s eyes changed, tensed for the inevitable attack that would follow. Katsuki started to move, weaving his swords through the space between them so fast that Izuku could barely keep up. He steadily drove Izuku back towards the trees, knowing it would be easier to pin Izuku and win. Izuku fought back with everything he had. He called upon the storm that brewed beneath his skin, allowing the chaotic energy from it to aid the speed of his strikes.


Suddenly, Izuku was pressing forward and Katsuki was the one left retreating. Katsuki breathed hard as each blow from Izuku’s sword felt like it had the power of an avalanche behind it. He was sure that his body would be sore for days after this, and he relished in the knowledge of that pain. Still, he wasn’t going to give up just yet.


In the end, it was Izuku who managed to pin Katsuki against the tree. Katsuki had been so focused on parrying the blows, waiting for his chance to deal the final strike, that he hadn’t noticed how far he’d been pushed back. The shock of his back connecting to the tree was nothing compared to the jolt that went through his body as Izuku pressed up against him, invading his space to look him square in the eyes with the reckless strength still bright in his emerald gaze.


“I win.”


Katsuki shivered at the husky tone of Izuku’s declaration, the Alpha in him roaring in agitation at being pinned by the Omega. He was supposed to be pinning Izuku . He’d failed to prove his strength to his potential mate. He would work harder to get stronger a little longer. He wanted to be at his best for Izuku when he offered to claim him.




Katsuki glared at Izuku with his usual scowl, “Yeah, yeah. You win. I’ll cook dinner.”


Katsuki attempted to shift away from his pinned position only to be held in place by Izuku pressing harder. He looked back at Izuku with a complaint poised on his lips that died instantly. Katsuki couldn’t parse the emotion that swirled in dark forest green eyes, but it captured him instantly. Any drive to move away, to blow off the loss, disappeared in an instant. Izuku was looking at him like he was cornered prey, possession clear in his gaze. He suddenly felt small, like those eyes had sapped all the strength he’d come to rely on, stripped down to nothing but Katsuki.


This was his moment. This was his chance to tell Kacchan how he felt. He’d dreamed of this moment so often that he was barely aware of his lips moving, speaking the words that he’d said to the Alpha in his dreams many times over. He felt a strange sense of detachment, as though he was viewing it from afar, like this was a dream.


“I want you to be mine,” Izuku’s voice didn’t falter as he spoke, the knowledge that the only way to prove to Katsuki that he was serious was to show him dominance keeping his tone sure and steady. “I want to be yours. I will follow you to the ends of these lands, I will have your back in every battle. I want you to understand how much I love you, and how long I’ve been waiting to say these words.”


The possession was palpable in his voice, giving it a rough quality that aroused Katsuki in a way he’d never felt before. He felt as though the breath had been knocked out of him. Izuku, the mumbling nerd that recorded their adventures down to the last detail and who would get flustered at the smallest things, was proving that he was strong enough to be Katsuki’s mate. Maybe Katsuki had been focused on the wrong things as he tried to come to terms with his feelings, but he couldn’t regret it either. Not if it brought them here.


Izuku dropped his sword into the snow next to them. He encouraged Katsuki to release his hold on his own swords, the clang loud as they landed on top of the sword already there. He pressed even closer to Katsuki’s warmth, his gaze still locked on Katsuki’s crimson one as he peeled off his gloves and discarded them to the sword pile.


He watched as Katsuki’s eyes darted down to his now bared hands, a crease between his eyebrows as he tried to understand Izuku’s intentions. He had no intention of keeping Katsuki guessing though, so he raised his hands between them slowly. He allowed Katsuki plenty of time to stop him as he gently cupped the Alpha’s face between scarred fingers. He wanted to burn this memory into his skin, wanted to remember Katsuki’s warmth blasting the chill on Izuku’s fingers away. Katsuki’s crimson eyes made their way back to Izuku’s own leisurely.


“Katsuki Bakugou,” the strength and determination in Izuku’s voice spoke directly to the Alpha in Katsuki. “I want to be your Omega. I want to be your mate, want to have kids and grow old with you. I know I’m doing this backwards, usually it’s the Alpha that exerts dominance to a potential mate, but-”


Katsuki’s growl cut his rambling off. He took a deep breath and closed his eyes for a moment to get his bearings. He was almost there, almost to what he’d needed to say since they first met.


“I want you to claim me.”


Katsuki was stunned. He’d had no idea that Izuku felt the same as he did. He constantly teased the green haired nerd about being so dense, and yet here he was trying to think back to all the little hints of Izuku’s true feelings throughout their time together and seeing them in a new light. Maybe he should apologize for the teasing.




Nah, the nerd was still an embarrassing nerd.


“I accept,” Katsuki said without hesitation. He leaned down and brushed his lips against Izuku’s chapped ones. He didn’t miss the shaky exhale from the shorter man before Izuku returned the kiss. Izuku’s hands fell to Katsuki’s vest, fisting it to bring him closer even as Katsuki’s hands gripped Izuku’s waist and pulled him impossibly closer. There wasn’t a whisper of space between their bodies now, and the thought had his Alpha instincts demanding he do it, he claim the Omega right here, right now.


Katsuki pushed back against his instincts. He wouldn’t let his hormones rule him, he wanted to do this right. Izuku was his one true mate. There would never be another being in this world that would mean what Izuku does to Katsuki. He could hold off on taking his Omega to ensure that he’s well taken care of first. It didn’t stop him from angling his head and deepening the kiss, though.


Izuku could smell the arousal in Katsuki’s scent, knew he was giving off his own powerful pheromones as they indulged in touches they’d wanted for so long. He opened his mouth, welcomed Katsuki’s tongue with his own as they devoured each other.


Katsuki pulled away roughly, panting as he tried to think through the haze of lust clouding his mind. They were only kissing and it already felt overwhelming. Izuku’s eyes shined up at him, the emotion Katsuki now recognized as love welling up and spilling over like the tears tracking down Izuku’s face. He couldn’t help the genuine smile that curved his usually downturned lips.


“But first, dinner.”