They have nothing in common.
He's a poor boy, while she's a pureblood, always prancing about in her velvet and lace; flaunting the ripe curves of her body while dripping with disdain for those whose heritage is less than whole. Black is her hair, her heart, her legacy; she never tires of telling him. While she thinks herself practiced in this woman's game, so safe in preconceptions pulled tighter than corset stays, Severus can see her intimations are as flimsy as her bodice lace. Black is her curse: a double-edged blade forever dangling above her head, staining her in its long shadow.
She is older, almost a lifetime older to someone his age, and like the star for which she was named, Bellatrix burns brittle and enigmatic from an impossible distance. While her heavenly body may orbit forever beyond his reach, Severus never tires of gazing beyond the binding horizon, reaching into that mysterious ether with his mind to caress a host of precious, forbidden things. Black is her magic but he is still so young, so naïve. In a world where all curses can be broken, a figurative blade cannot make him bleed.
The day is already old, the sky as glaucous as the slush in the street, when she Apparates outside his tiny cottage in Spinner’s End. This slum, this low place was what her mind grasped as she turned on her heel, her father's words still ringing in her ears. Her life is over: she'll be married to a stranger in three months hence—what's one stranger more?
They are not friends...
Rage ripples beneath her skin, white and cold as the sparks of static that crackle in the silken folds of the cloak she unties and shrugs to the floor.
Severus, no stranger to fury, is not afraid. Anger, like magic, is just another force seeking a channel: control and release. His mother is dead; his own loss, a grief he cannot articulate (if indeed it even is grief; at times seeming more like a cross between remorse and relief), feels like sludge in his veins, an ice foot's slow, deliberate contraction around his heart.
The fire in the parlor grate gutters; clouds swallow the last of the sun, while falling snow renders the boundaries of earth and sky indistinguishable; and two strangers suddenly find themselves chafing in the vacuum of silence between each tick of the mantle clock in a cold and empty house: fallen star and slumlord; together, alone.
Her dress, the color of banked embers, slides off one shoulder. He tries to swallow, but finds his throat has turned to ashes. Their eyes connect across a charged space. She licks her lips.
He doesn't know why it happens. She doesn’t know who started it, but once he's buried inside her, grinding his hips into hers, his tongue tracing the curve of her ear, the hollow of her shoulder, and plumbing the tropic of her mouth, what does it matter? Their bodies, displacing the desolation of the room with desperate, wordless syllables, unite with the single intention of unraveling all secrets of the universe and closing the impossible distance between them through the simple instance of a shuddering alchemical reaction: the shock of skin on skin, the pleasure of lips and teeth and tongues.
No spell, no potion, has ever made her feel like this. His body, all angles and sinew over bone, is maddening, pale perfection, his sighs softer than the shadows that creep and lengthen around them. She cannot control the desire that bursts from her open mouth, each cry gusting heat in the freezing room. She cannot contain the trembling, the quaking that erupts from her inner recesses and the hot, musky slickness between that begs him, commands him. Bucking against him, nails digging into his backside, her screams shake the plaster from the walls—
He moans, spilling his fluid heat into the unseen as she shatters around him, emptying himself deep, so deep inside her, while riding the waves of their shared decrescendo to something that is neither completion nor contentment.
Both feel pain in the growing absence, the burning when he finally pulls away: a hollow born from the ghost of a blade.
They make no promises.
Promises are for lovers.
He smooths the wrinkles from her dress, her cloak, and kisses her tenderly one last time. Turning on her heel, tossing a haughty smile over her shoulder—A ha’penny for your thoughts—she disappears with a sound that rings like steel in the moonless dark.
She never tells him he was her first.
Or the rest—
The woozy mornings after, the pennyroyal for her tea, the secret crimson spiral: the private hell she would not put in a Pensieve, fearful of who might see the half-blood stain upon her maidenhead, black as her destiny.
When they meet again, there is too much bloodshed between them, too much ink beneath their skin to rebuild that bridge. And if he remembers, his eyes betray nothing.
Years later, when she is alone again in another cold house in another cold bed, lying beside another who is not a friend and who will always remain a stranger, sleep will not come. Rising, she creeps to the window and peers through the dark glass. The moon, riding high, bathes the contours of her now white and silent world in a shade that is neither grey nor blue.
It reminds her of a narrow street and cobblestones. But memory's caress, soft as a snow and every bit as cold, stings as it melts into the skin of her past, and black is the confession she gives to the night, the secret she will never tell another living soul about a lover forever lost to the long-away and far-ago—
It should have been you…
She whispers his name. Its syllables, landing against the glass, fog and then, quickly fade, like echoes of a dying star.
She wonders if he ever really knew.