Chapter Text
James Potter was going to be an alpha. That was a fact as much as the sky was blue and the grass was green. Except for the fact that James still hadn't presented and he was beginning to think he was actually a beta which was fine… just a bit unexpected. Sirius had presented first in their second year, an alpha, proud and tall. After that had been Remus, also an alpha which was unsurprising - most werewolves were alphas unless they were turned later in life. Peter and James still hadn't presented, although Peter seemed happy as a beta. Both his parents were and he wasn't particularly fussed about sex and romance so being a beta suited him. There were no ruts or heats to worry about.
But there were also no mates.
That was the part that James really wanted. He was a romantic and the idea of being part of a bonded pair had always fascinated him. The way their magical cores entwined, both alpha and omega became stronger for it.
Not that they were meant to bond at school. There were heat rooms built specifically in each house area to keep omegas separate and safe during heats. To James it just felt like a leftover from the pureblood culture of arranged marriages between alphas and omegas. He didn't see why they couldn't be allowed to bond if they knew they were right for each other.
He was going to bond with Lily. There was no doubt about it, especially after she'd presented last month as omega. James just needed to hurry up and present. He'd already figured out how to court her formally, practising his dancing and starting the perfect collection of nesting materials. He'd even been learning to cook from the house elves. James was a catch and he knew it.
His body just needed to catch up.
And catch up it did - but not in the way anyone expected.
In the middle of their fifth year, not long after James' sixteenth birthday, he woke up nearly feverish and soaking wet. Slick covered his thighs and arse, and the boys' dorm stank of sex.
More importantly - the scent of one Sirius Black.
James couldn't remember thinking of his best friend as hot before, but now, as an omega, his brain was connecting dots that had always been there but ignored. He wasn't exactly happy about his new lot in life, always seeing himself as a protector and a fighter, but there was no changing fate.
And at least he'd get to mate.
"Urgh," James groaned as he ran his fingers through the mess on his thighs. It was sticky and uncomfortable, but mostly he just felt a weird ache, an emptiness inside him that was begging to be filled. "Fuck."
"Prongs? Oh shit!" Came the response from Sirius’ bed. "You smell good."
"Says you!"
"You're… an omega?"
The curtains flew open and silver eyes bore down onto him, intense like fire.
"Apparently so," James muttered, barely resisting the urge to shove his fingers up his arse. His face was burning hot as he let his gaze roam over Sirius' body, taking in the quidditch-toned muscles, the shock of raven hair, the pale skin of his neck just waiting to be bitten and adored.
James was unable to tear his eyes away from his best friend. He'd always known objectively that Sirius was attractive, but they were both going to be alphas. They weren't compatible. Sirius had never been an option. Only now he was. And he was the only option James wanted. There was no one else in the wizarding world and beyond that cared for James like Sirius did - no one else that James cared for in return. Even if James had been an alpha, any omega he loved would have come to realise they were a package deal.
The puzzle pieces seemed to slot into place the more he thought about it. James and Sirius had always been closer than any of their friends. The two alphas had a tendency to butt heads over any sort of decision, but Sirius practically purred whenever James stole his jumpers, or even, at times, his wand.
Fuck. James really had been blind. No wonder people assumed Gryffindors were stupid.
Sirius' scent spiked again and James let out a soft moan as he felt even more slick leaking from him. The scent of alpha had always been pleasant, but Merlin, he was in trouble.
"W-where are the others?" James whispered.
"Already at breakfast. Must have left before this hit. Otherwise Minnie would have already dragged you out to the heat rooms."
James bit back a growl. He didn't want to go to the heat rooms. Whilst he knew there were plenty of toys and supplies for making heats as bearable as possible, he didn't want to be alone. No. He didn't want to leave Sirius.
"And you?" He asked his best friend, the tension suddenly thick between them.
"I-" Sirius' nostrils flared and his eyes were dark, hungry as they fixed on James. "I am doing my best."
And he really was. A lesser alpha would have given in to their desires by now, especially a pureblood. They were raised with a sense of entitlement that could be devastating to an omega in heat. But not Sirius. Even with the stench of omega heat filling the room, Sirius was keeping a respectable distance.
Which just wouldn’t do.
"Well… you always have been my best mate," James murmured, letting his gaze fall very deliberately to Sirius' lips.
Sirius whined, his resolve snapping, and James found himself with a lap full of alpha. Legs tangled around his waist. Their lips crashed together, all tongues and teeth. The rims of James' glasses cut into his cheeks, and his hands pulled into the thick tresses of Sirius' hair. The musky scent of alpha surrounded him, driving him crazy as he tore at Sirius’ boxers. There were too many layers and James needed Sirius in him like five minutes ago.
“Off,” he growled and to his delight the alpha complied, sitting up and wriggling out of the offending garment.
Then they were kissing again. Sirius’ fingers tugged at James’ hands, pulling him closer. He nipped at James’ lip before trailing kisses along the length of his jaw, down to his neck, his teeth ghosting over where the mating bite would go. James shivered at the sensation, tilting his neck to give the alpha better access. The haze of heat was pushing his body into overload. All he could think about was the need to mate, the emptiness at his core, as he rutted helplessly against the alpha in his lap.
“More ,” he whined, letting his nails scrape down Sirius’ back.
“F-fuck… James…”
“ More! ” he insisted, biting Sirius’ shoulder to make his point.
With any other alpha he would have made them work for it, the way he’d been planning to court Evans, but this was Sirius. No one knew James better than Sirius. There was no need for courtship or dancing or mating gifts. They were already the best part of each other, and now they could make it official.
He bit Sirius again just to make sure. The alpha growled and shifted on the bed so he was settled between James’ legs, digging his teeth into James neck as his cock finally pushed inside him, stretching James around the thick girth and both omega and alpha moaned in glorious harmony as Sirius bottomed out. It was… everything. James hadn’t realised just how good it could feel. He whined again, bearing down on the cock inside him, rutting up against it. The pain in his neck quickly subsided as Sirius licked over the wound, and James could feel his magic start to entwine with Sirius’.
“Oh, Merlin…” he gasped, squeezing his eyes shut as Sirius started to thrust into him.
The movements were hard, messy, mindless. There was no skill or talent, just the base need to mate and bond and fuck. With every thrust James met Sirius halfway, moaning loudly. It was like nothing he’d ever felt before. Pleasure coursed through him like a river, flooding his senses. Heat coiled at his core, and it felt like he was losing control. Nothing mattered except the building pleasure twisting and tightening inside him.
“Sirius, please,” he moaned, not quite knowing what he was asking for.
“Fuck! Jamie… Merlin, you feel so good, smell so pretty, and mine,” Sirius purred before capturing James’ lips in another kiss.
His tongue slid into James’ mouth, minty from brushing his teeth. James let his tongue glide against Sirius’, tasting and searching and exploring until they both had to break for air. The alpha panted against his cheek, as the thrusting grew more and more erratic, and his knot began to swell, catching on James’ rim with every snap of his hips.
Oh and that was it. What he was craving… that something more. Not even Sirius’ cock could take away the emptiness inside of James. No. He needed his alpha’s knot to sate the waves of his heat.
“A-alpha,” James keened, clenching down on the knot as it swelled inside him. “Please, alpha, Sirius.”
“Mine!” Sirius growled again, and with one final howl he forced his knot into James, locking them together as he came.
Fucking fiendfyre… James had never felt so full. All it took was a few firm strokes to his cock and he was following Sirius over the edge, spilling onto his stomach as Sirius rutted into him, working them both through their orgasms.
James cupped Sirius’ cheek in his hand, catching the alpha’s gaze. His glasses were askew and fogged up, but he could still see his lover clearly. Despite the aching bite on his own neck, he needed to check before he made his move. One bite formed a connection between an alpha and omega, but one that could be broken. Two bites was the mating bond that would last for life.
Not even James would rush head first into that without checking first. He wouldn’t trap Sirius. He couldn’t.
But Sirius just nodded, smiling brighter than the star in the sky. “Do it.”
So he did. James brushed his nose under his alpha’s jaw, pressing a kiss to the pale skin before sinking his teeth in. The taste of blood filled his mouth, and he grimaced a little. It was… unpleasant. But just as Sirius had done with him, James licked over the wound, knowing that his saliva would help to heal it. As he did, their magical cores bonded, and James became more and more aware of the brilliant wizard above him. It wasn’t a telepathic bond, that was a myth or a fantasy written in fiction, but James could feel Sirius in his heart and soul. He could feel the echoes of his alpha’s pleasure, the purrs of contentment as if they were his own.
They were one.
As it should be.