A/N: this was a request i got over on tumblr and thought i'd post it here as well. i own nothing and blackinnon makes me sad. enjoy!
They find each other at night, the two of them sitting at opposite ends of the Quidditch stands. It's well past curfew, but they're in their seventh year and no one really cares. Besides, it's not much safer inside the castle than out of it, not with the all the Slytherins running around, preaching the gospel of a madman.
There's a cigarette in her mouth, and she supposes that's what summons him- only moments after she lights it, he's next to her, smiling, and she passes the cigarette over to him, smiling back.
The smoke creates a wall between the two of them- keeping her safe, she thinks; keeping him out, he thinks.
"Alright, McKinnon?" he asks, stretching back against his seat.
"I'm fantastic, Black," she says. "Thanks for asking."
A silence falls between them. They don't know each other very well, but there's enough familiarity between them for it to not feel strange. She doesn't like the quiet, though. When the world is quiet, her mind is loud.
There's a glint in her grey eyes- a wicked glint, a beckoning glint, a glint that screams, I AM NOT AFRAID- as she stands. He stands with her, and when she screams so loudly it hurts his ears, he screams right back, and he swears they can be heard across the world.
She falls back into her seat, and he thinks, this girl is a thunderstorm, wild and deadly and far too easy to fall in love with.
As she lights another cigarette, she glances at him from the corner of her eyes. What she thinks is, this is a boy more dangerous than any murderous and fanatical supremacist. What she says is, "I guess you're decent, Black."
They smirk at each other, and it feels as though they've told each other secrets they didn't even know themselves.
Sirius Black is not to be trusted, she tells herself in the month that follows.
Marlene McKinnon is positively mental, he tells himself in turn.
This doesn't stop them, though.
He finds himself unable to stop watching her, waiting for someone to make her laugh and studying the way her eyes scrunch up and how the freckles on her nose bunch together when she does.
And she watches him as well, paying attention to how he acts around his friends and how defensive he gets over them. She smiles when she catches him standing up for her little brother.
It doesn't go unnoticed.
The seventh years- excluding the Slytherins, for obvious reasons- are all gathered in the Room of Requirement, and it's sometime between three and five in the morning, and she's almost asleep when she hears Lily murmur, "What's up with you and Sirius?"
Marlene rolls over in her sleeping bag to face the redhead, a hint of blush on her pale cheeks. "Nothing," she says defensively, and Lily snorts. "Alright, then, what's up with you and Potter?" Now they're both blushing.
The conversation stops there, but Marlene doesn't miss the look on Lily's face when, not long after, Sirius drags his sleeping bag over and curls up so close to her that she can feel his warmth.
When they wake up the next morning, her head is on his shoulder and his arm is over her stomach, and no one says anything.
As per usual, the New Year's Eve party the Gryffindors host is intense, and she has to disappear into the dark corridor to escape. She can't handle it; the noise, the people, the movement- it all makes her want to run and hide, far, far away from any forms of life.
And he's there- of course he's there. Barely a minute after she departs, he's in front of her, and she's too aware of his chapped lips in the cool air. She wraps her arms around herself, trying to keep warm, and stares at some place over his shoulders, anywhere but at him.
The party is so loud they can hear it from outside as they begin counting down to midnight. It gets louder and louder the closer they get, and when they get to zero, she whispers it with them, and then his lips are on hers and she's pressed against the wall behind them. His hands are tight on her waist, and where his fingers touch, it burns.
They have to leave soon after that, and they don't see each other for nearly a year. He busies himself with fighting in the war, and she busies herself with ignoring it. Letters from him arrive at least twice a month, but she never opens them.
It's in Diagon Alley that they meet again. The first thing she notices about him is that his hair has grown out even more; the first thing he notices about her is that she cut hers off. They realise with mutual horror that they don't quite match as they once did. He's a little too alive, and she's a little too cold.
They don't fit.
"Hi," she says after a tense moment. She's sitting at a table outside a small cafe, her long legs crossed in front of her. A smile on her face, but her eyes are empty.
As he sits down across from her, he doesn't say hello, or ask how she is. He doesn't say a word- he doesn't have any.
When Marlene stands up, Sirius is silent as she leaves.
The wedding of Lily Evans and James Potter is a small affair. They stand at the altar with only twenty or thirty people in the seats facing them. The priest pronounces them man and wife, and their happiness is infectious.
Marlene, standing behind Lily with a bouquet in her hand, smiles, and Sirius doesn't miss it. He's cut his hair, and hers has started to grow back, and they're the same again.
At the afterparty in Marlene's apartment, she finds herself sitting on a kitchen bench with a bottle of firewhiskey in her hand. Sirius is with her, raiding the fridge and demanding to know why she doesn't have any peanut butter.
"Because I'm civilised," is what she tells him, but her mess of an apartment begs to differ. "So, Black, how are you?"
He shrugs. "Pretty shit," he admits, not bothering to hide a grimace. "You?"
"Pretty shit."
And then she laughs. She laughs so hard her stomach hurts and she laughs so hard that Lily yells from the living room for her to shut up. Wiping tears from the corners of her eyes, she isn't quite able to wipe away the grin still etched upon her face.
"You know, you scare the hell out of me sometimes, McKinnon," he says flippantly. "I think that's why I love you so much."
Marlene squeezes her eyes shut so tightly that she sees a kaleidoscope. When she finally opens them again, she's beaming. "I guess you're decent, Black."