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Rin was probably an omega – that was what Sae thought anyway. Everyone around them had already pinned the alpha label on his little brother because of his performance on the field, but Sae knew they were wrong. Even years away from Rin’s presentation, it was obvious to him, a certitude that couldn't be shaken off easily. As obvious as his own alpha designation was when he was younger – though he has only just presented, earlier than most kids.
It wasn’t that Rin was fragile – since getting into the team, he’d filled out, grown up, and didn’t fly away anymore when getting body slammed on the field – or delicate – if anything, he was still a little rough around the edges, a little too destructive for his own good – like the omegas on TV or in books, far from it even, but that didn't change Sae’s opinion. It wasn’t about Rin himself, but about one of his habits – and his scent.
You weren’t supposed to know what you’d present as until reaching adolescence save for some early bloomers – like Sae who, still on the cusp of childhood, had to lock himself in his room for a week when the pains of his first rut started gnawing at his gut – even if there could be signs. If these signs were real or simply an amalgamation of clichés, Sae didn’t really know – didn’t really care as long as it didn’t affect his (and their) ability to play football.
And it didn’t. Not really. A little perhaps, in the sense that they were left alone for most things and their behaviors not scrutinized too harshly – a bit of arrogance had never been bad for alphas and their plays certainly earned them a bit of leeway when it came to their perceived rudeness – but that was just par for the course for the Itoshi brothers. Perhaps that was why nobody noticed the ways in which the Omega inside Rin presented.
Rin was the quintessential little brother – entitled to Sae’s time and affection as well as his personal time, always following his every step, spoiled at his core – but that alone was normal and Sae had no reason to refuse him anything. The things that tipped this from “needy younger brother behavior” to “Omega behavior” were occasional – but very noticeable. And Sae noticed it all.
* * *
Next to him at the dinner table, Rin was digging into his omurice, not eating it, instead playing around – breaking the soft yellow omelet and taking out the chicken rice inside to spread around his plate. Their mother had told him to stop a few minutes ago with Rin only answering with a vague nod, but since then she had only looked on, her eyebrows furrowed in worry. Sae swallowed the last of his food, watching Rin from the corner of his eyes. If their father were here and not in the middle of a work trip, he'd probably have done the same as them, observe Rin in silence.
Again . These bouts of absent-mindedness (though Rin’s head was more often than not in the clouds usually) had become something of a habit recently, always accompanied by a slight fever. With the temperatures dropping and the weather slowly turning more and more wintry, it was expected for one of them to catch a cold, but it wasn’t that – Sae knew it.
Going unnoticed by their mother, a cloying, almost oppressing scent filled the air, turning Sae’s insides all gooey. He looked away just as Rin’s cheeks flushed pink, his small tongue peeking out from his lips. The sip of water Sae forced down his throat did nothing to help quench the thirst.
“Sae,” their mother called softly and when he turned to face her, she offered him a gentle smile. “Take Rin upstairs, okay? I'll bring some medicine later.”
Simple cold medicine wouldn’t do much for this, but he nodded anyway. “Sure.”
The bunny-shaped apples that were placed on the kitchen counter and that Rin sounded enthusiastic about this evening when their mother was cutting them, were quickly placed in the fridge for tomorrow’s breakfast as Sae took Rin’s hand in his to drag him upstairs. His little brother's hand was warm, a little too warm even for his usual child-like temperature. The telltale sign that Rin was out of it was his lack of enthusiasm as being led around by Sae – he simply walked behind him, his eyes unfocused, almost tripping at the end of the flight of stairs.
First stop was the bathroom where Sae pushed Rin in front of the sink before handing him his toothbrush and the toothpaste that he didn't take. Instead, he looked at it then at Sae who sighed – when did his little brother become so spoiled? – as he took them in hand. Rin obediently opened his small mouth as wide as possible and waited with his eyes closed.
That was something their parents had forbidden Sae to do when Rin was still little, unable to do it properly by himself and relied on his brother even more than now, but he didn’t dislike doing it. After putting toothpaste on the head of the toothbrush, Sae cupped Rin's face with his free hand, holding him into place – a little too forcefully if the yelp Rin let escape was any indication – and started his work as gently as possible with his trembling hands.
Rin still had a few milk teeth, tiny among the others, and a hole where one of them had stood last week before it fell out. None of them were sharp, unlike Sae’s, whose fangs had grown in during his first rut and with which he still cut himself when he didn't pay attention and bit his lips, but soon. When Rin would present as an Omega – in a few years, after his youthful body had grown a little more – two fangs would appear, right where Sae was brushing now. Sae had refused to use a teething toy, but Rin liked biting things so he probably would… He let out an amused sigh at the thought. Taking extra care of this area, Sae cleaned it as much as possible, pressing with a little more strength to see if he could feel the future fangs under the gums – Rin tried to shake his head away to no avail.
A fillet of foamy saliva spilled out of his little brother’s mouth, and he directed Rin's face toward the sink so he could spit. It should be over soon, but, just to make sure, Sae made Rin open his mouth wide so he could peer inside. A few more strokes around the back of his mouth earned him a gargled “Nii-chan” as tears formed at the edge of Rin’s firmly shut eyes, but Sae let go of his face to pat his head and the pain was seemingly forgotten. His baby brother was nothing if not resistant to the pain.
Under the familiar smell of the melon-flavored toothpaste, the sickly-sweet scent from earlier grew stronger, making Sae slightly dizzy. Once again, he let go of Rin’s face to touch the back of his nape. Damp. Warm. Far from a simple fever too. No, that was closer to…
“Rin, here.” Holding out a glass of water to Rin, Sae urged him to drink and spit out the rest of the toothpaste foam. “Hurry up.”
Despite his dizziness, he picked up on the sounds of their mother’s steps approaching so he let go of the glass once it was in Rin’s hands and took his own toothbrush to pretend he was doing something other than brushing his brother’s teeth. Even if he looked sick, Rin still had to do things by himself – or so their parents said. The bathroom door opened, and their mother appeared, holding out a small package of medicine.
“Sae, you’ll stay in my room tonight, okay? I'll sleep with Rin.”
She meant well – when Sae was younger, she’d also sleep next to him to keep him company through fevers and colds, but–
“No need.”
Not today.
“It’s not that bad.”
“Are you sure?”
“There’s no practice tomorrow so I don’t mind if Rin wakes me up during the night.” He searched for another thing to say and ended with a fake-sounding “Plus, you worked all day so you’re tired right? You should rest too, Mom.”
“Is that so…” Her words were hesitant, but, looking at Sae, she smiled. “Ah, is that what the doctor talked about when he said you’d start getting territorial? You don’t want me coming near your room?”
“That's–”
Not entirely wrong.
His mother stroked his hair. “Sorry Sae, I didn’t consider your feelings. I'll come check first thing in the morning, but don’t hesitate to wake me up if something happens, okay?”
“Hm.”
“Good night you two.”
After patting Rin’s head, she disappeared into the hallway and Sae sighed. It wasn’t like she was wrong. She wasn’t technically, but missed the mark a little. His bedroom wasn’t the thing Sae was territorial about.
“Rin.”
“Nii-chan?”
“Here.”
He popped a little pink pill out of the medicine package – strawberry-flavored, Rin’s favorite – and slipped it past Rin’s half-open lips, their warmth clinging to the tip of Sae’s finger. It took a few seconds for Rin to swallow, and when he did, he stuck out his tongue to prove the pill was gone. The sight made Sae stop in his tracks even more than the now enrapturing smell closing in on him.
“Good job, Rin.”
The only answer he got was a sleepy nod and Rin let his head fall on Sae’s shoulder, ready to get carried to their room. It was only a few steps away from the bathroom, but Rin didn’t make it easy – not content with being almost as tall as Sae now, he was heavy too. But Sae didn’t falter in his steps – even with Rin half-asleep, showing any kind of weakness was unbefitting of the super cool older brother he was supposed to be. Once there, Sae locked the door and sat on the bed, opening his arms wide so Rin could hug him properly.
“Nii-chan,” Rin said, his voice tinged with sleep and fever, barely a whisper in the silent room, “don’t move.”
For as long as Sae could remember, it had been the same. Whenever Rin felt under the weather or had been scolded a little too harshly, he’d take refuge in Sae (or his clothes if he weren’t here). He’d tuck himself in Sae’s embrace, wrap his arms around his brother’s back, and nuzzle his neck. Then and only then would he calm down a little and sometimes even drift to sleep. It was manageable when they were younger but less comfortable now that they almost had the same height though Sae made it work – for Rin. For himself too.
With Rin seated on his lap, Sae leaned back until he was fully lying on the bed with his brother sprawled on him, all boneless and limp and warm. He was all wrapped around Sae now, his still-a-bit-scrawny legs entangled with Sae’s and his arms holding him tight. The scent surrounding them shifted, as syrupy-sweet and enticing as before, but now tinged with satisfaction even as Sae’s blood burned inside his veins.
More than this habit of making a nest out of Sae's body – because what else could it be really, when keeping close to Sae's scent was the only thing calming him down – the thing that pinned him as an Omega in Sae's eyes was even less subtle.
After all, the sweet scent that had been wafting in the air for a while now couldn't have come from anyone other than an Omega. Their parents were both Betas so it wasn’t strange that they didn’t feel it or even entertain the thought of heat-spotting, as Rin’s body prepared to transform – especially after Sae presented and Rin seemed to follow his every step – but nobody else seemed to detect it. He didn’t know why, didn't care much about the reason that much, but it was better this way.
Rin wasn’t just an Omega. No, of course not. There wouldn’t be any meaning to Sae’s actions if he were just his baby brother who happened to be an Omega. Just like they completed each other on the field, they did so in their everyday life too. Sae and Rin. Together they’d be the best in the world, and together they’d stay until the very end. Even when he was still a baby, Rin clung to Sae – a big brother’s boy from the start – so he understood this too. Rin wasn’t just a simple Omega – he was Sae’s before anything else.
“Rin.”
The soft sounds of Rin breathing peacefully were enough of an answer – he had finally fallen asleep. Sae disentangled from Rin’s embrace, not to climb to his bed on the top bunk, but to look at his brother from the side. Propped up on his elbows, he observed Rin sleep. At his age, Sae had lost almost all his baby fat, but Rin’s cheeks were still round, full, and soft – he poked the tender skin, and watched as Rin drooled on the bedsheets. Then moved by an irrepressible desire, he leaned in and gently bit where Rin smelled the sweeter – his nape, covered by a mess of hair damp with sweat. His pheromones were still weak, barely developed, but under the familiar uniquely Rin scent, there was a bit of Sae too in there, clinging to his skin. Rin didn’t wake up, but a tremor shook his body at the contact. Not yet. He probably wouldn't present as early as Sae did – Rin always did things on his own terms. Not yet, but soon enough.
And just like Sae waited for Rin to start football so they could play side by side, he’d wait for him to join Sae on the path to adulthood too.