The first time they kissed was at Hogwarts.
They had been sitting under the big willow beside the lake, and Andy was laughing. It had seemed like Andy was always laughing back then, her dark eyes gleaming with delight at the world around her. But now she nevernevernever laughed.
She had seen her lit behind by the glow of the sunset, and it had suddenly struck her how truly beautiful her sister was. She had lunged forward, stopping scant inches from Andy's face. She had looked into the eyes that were a mirror of her own, and she had seen… curiosity. And it had become so much more than that.
It was true that there was a darkness in both of them, as there was in all true Blacks. But when Bellatrix thought of Andy, she knew that the creeping shadow that infected them all wasn't a part of this. Nothing could tarnish the love they held for each other.
Andy was love and light and laugher. Andy was red-painted lips and coy smiles from beneath eyelashes. Andy was a sidelong glance in the Great Hall, beneath everyone else's noses. Andy was everything. Would always be everything.
Andy was a Ravenclaw, but used her intelligence to sneak into the greenhouses to weave flowers through Bella's long hair, the scent of night-blooming roses permeating it for days afterwards. She used it to find a way to literally bottle her laugh when Bellatrix had expressed such fascination with it. She used it to devise a for-their-eyes-only ink, unlocked by the tiniest droplets of blood imaginable. Those were the days when their afternoons were full of letters – love and lust mingling until they couldn't help but meet despite the fact that it was daylight.
Inky fingers would intertwine until you couldn't tell where one ended and the other began. Hot breath fanned on faces, on legs; tongues and teeth exploring and testing each other in a dizzy haze of longing while fingers traced delicate paths that raised gooseflesh in their wake. Hair would splay on pillows, on grass, even on the benches in the quidditch changing rooms, brown mingling with deepest black.
Somehow their need for each other only increased until it was all Bellatrix could see. It was all she wanted to feel – to breathe Andy in more and more, until they were as united as was possible. Sometimes she thought they would devour each other in their passion. And would that really be so wrong?
They saw each other often, cutting classes in their pursuit of a specter of a life that could be lived, a life Bellatrix desperately wanted for herself. For what would be more fulfilling, more ideal, than Blacks united in pursuit of a perfection that could only be found in each other?
They would embrace the darkness and madness that awaited them, and it would be glorious ruin and devastating possibility. The would be the Queens of all they surveyed, Andy's laughing mouth leading Bella's fiery eyes.