Sirius wasn't sure of when it had started; and if he was being honest with himself, he didn't really know what it was, exactly.
He knew there was something there since the first time he'd laid eyes on James Potter – after Sirius had been seen off by his father at the Hogwarts Express platform, having gotten a stern 'now you behave, young man' en lieu of a warmer goodbye. He'd met James in one of the first train cars, crouching down by his school trunk in the middle of a crowded cabin, talking excitedly to a bunch of other kids about how he'd gotten that one scar on his knee.
Apparently, his parents believed in letting children climb trees, and on leaving their cuts and scrapes heal in a way that left marks. 'Da says they make you interesting!', he'd heard James explain, and that was all it took.
To eleven-year-old Sirius Black, the ability to climb a tree was already enough to make someone interesting, but he would have never admitted it out loud. He had been taught to be proud of his achievements, yes, but a quiet sort of proud – and bragging about imperfections of all things was definitely out of the question.
See, to sixteen-year-old Sirius Black, James's Quidditch-toned back muscles were much more appealing than some old scar on his knee. They had climbed their share of trees together, and since then moved on to other kinds of mischief that made Sirius's parents threaten him with all sorts of punishment. Still, he didn't fear pain, or hardship – at least not any kind the Blacks could inflict. It was that sort of attitude that had landed their eldest son in Gryffindor, after all – though unfortunately it did not prepare him for the sort of ache only more subtle matters could produce. The sort of bubble-like lump in the back of Sirius's throat, that seemed to get stuck there every time he watched James for too long, had come to stay sometime around third year, for example. It made life difficult to navigate in such a different way from what he'd been used to that Sirius had no idea of whether he was pained or thankful for the end of the school term.
"We'll see each other soon, okay? My parents say you can come by whenever you want! Just hang on tight for a week or two and we'll Floo you over, yeah?" James had promised, one very warm hand on Sirius' shoulder, and then he had left.
Three weeks into their summer holiday, and there they were, though: lying face to face somewhere in the Potter's estate where the grass was tall and much greener than the dry weather should allow. The sun shone high above them, and the prickly feeling of the drying lake water on his skin was just starting to become bothersome to Sirius, who hadn't thought swimming would be such a bad idea until he realised the amount of exposed flesh that entailed.
"So, do you think Evans might wanna go out with me next year? I know, I know, she keeps saying I'm a prick and that I have no manners, blah blah." James had started again, early afternoon sun probably burning Sirius's pale complexion as he tried not to stare at the path the water droplets trailed down the other boy's shoulder while he spoke. It was just unfair, how James's eyes would light up when Evans came up in conversation. It was already hard to ignore it when they were all at school and she would pass by all the time, making his best friend stop on his tracks to watch her – but somehow it was even harder to compete with a girl who was not even there. The image of Lily Evans in James's imagination was a standard Sirius could never achieve, and it became more obvious every day.
Still, Sirius would tell himself, at the same time, there was nothing keeping him from seizing the effects that Lily Evans brought up in James. He was free to bask in the sight of his friend's shy smile, thin lips curving up in a way that was so different from when he was working on an especially elaborate plan or prank. Not to mention the way he would run his hands through the hair he'd been growing, much to Sirius's delight, which still stuck up in every direction despite being wet.
"But she can't say no forever, can she? I mean, you think I'm a decent bloke, Pads. Right?"
Sirius nodded, as he always did. Evans was a smart bird, and he was sure she would see how great James was one day. This dancing around each other that they did would have to lead somewhere eventually, even if she insisted on being chummy with scum like Snivellus. Maybe Sirius could take responsibility for more of their pranks against him next year, or maybe he and James could find a way to hex him without her knowing it was them doing it. He was sure Moony could come up with a way to make them all better at non-verbal charms, and this way James could get what he wanted.
Because if Sirius was sure of one thing, it was that James Potter would find a way of getting what he wanted, and that he would be there to help him all the way.
Even if it meant losing his best friend – his brother, as James had said many a time, causing Sirius's stomach to do an elaborate flip, bile rising – to someone who had the one thing he couldn't offer.
"She'll see it soon enough," Sirius spoke softly, daring to brush a damp strand away from James' forehead, the tips of his fingers tangling into his hair. There was no need to specify was it was that Evans would see, Sirius thought, bubble lodging in his throat as it was bound to do sooner or later. It was hard to pull away when James himself wouldn't, and instead just closed his eyes and leaned into Sirius' touch.
James' skin felt hot against his own, and Sirius shivered.
They were so close, lying in the grass like that. Sirius' gaze traced the shape of James' eyebrows, the tiny round scar right below his eye, the curve of his nose he would never admit to being self-conscious about. Careful not to tug on his hair, Sirius pulled away ever so gently, feeling his heart leap in his chest when James seemed to chase the contact, tilting his head up and letting out what Sirius could only describe as a shaky breath.
It had to be his imagination, Sirius reasoned, letting his knuckles graze James' temple in an awkward caress. There was no way Prongs could want that, as there was no way they had moved closer; the next shaky breath shared by them both; Sirius' thumb right under the tiny round scar, sliding over his cheekbone.
"Jamie," Sirius called, and it sounded strangled. It sounded quiet, weak, as if all the courage in his body had been drawn to the hand in his friend's hair, leaving nothing for his voice to feed on.
Prongs hadn't been Jamie in a long time, hadn't been Jamie in school for years, but somehow it felt right for the occasion. Maybe as they lay in the grass like that, as Sirius' skin prickled not from the drying lake water anymore but from some sort of anticipation that made all of his nerve ends raw, with his mate's cheek under his palm like that – the name still fit.
"Hi." James opened his eyes, and it was almost too much. They seemed to bore into Sirius' head, read into Sirius' thoughts, leaving him ultimately open. He watched James' eyebrows draw close together, and prayed it was because of the sunlight.
Words had evaded him completely. Their noses touched.
Jamie 's lips felt soft under his own. Sirius was warm all over.
And there they were again: hazel eyes so bright Sirius felt like shielding his view from them. James' triceps were moving, his bare chest was pulling away and the droplets were still there, though now probably sweat, rather than lake water. Sirius desperately wanted to chase after them with his tongue, but they were way too far now.
"Race you to the broom shed!"
With an eyeful of James' bare calves, Sirius rolled onto his back and drew in a gulp of air, preparing himself to watch him run away. His head felt too light, almost alcohol-drunk. Sirius thought he would pass out if he tried to get up, and held onto the grass instead. James did not move.
"Come on, you tosser!"
James' fingers circled his forearms, pulling him up. Sirius' vision went blurry for a second, blood rushing back to his brain as he saw stars; a series of explosions not unlike golden, magical fireworks. He stumbled forward, and James' grip tightened.
Sirius did not fall.