There is a world for every possibility one can imagine.
And a soul, however broken, cannot rest until they have achieved their life's wishes.
Every soul gets that chance, for Fate is not discriminatory, nor forgiving. It simply is, and cares not for the woes and trials of man. To Fate, there is no hero, no story, and no villain.
There are souls, and their wants and needs, and what comes of that has implications which are obvious only to the human race.
One soul was sent to another realm of possibility, and told that he had the chance to do what he willed, with the knowledge he had. And there were consequences – whether they were good or bad is subjective to the view of humanity alone.
C'est la vie.
Chapter I – The Girl Who Was Spared
He had patiently waited for a few more hours than he had in his past life, and come while they were all in their beds.
He slit the adult Potters' throats as they slept, not knowing their fate. There was no Lily Potter with her sacrifice in this lifetime – there would be no Boy-Who-Lived, either - not if he could help it.
He moved into the next room, where young Harry would surely be asleep as well. Vulnerable. Defenseless.
A note of surprise came to him as he went into the nursery, and found a larger crib, twice as many toys, and two children instead of one. The boy was still there, to be sure – but now there was another infant, dressed in pink. It seemed that there were some differences in this timeline from the one from whence he came.
The boy began to wail and cry. The Dark Lord quickly silenced him with a Killing Curse, and felt a spring of joy awaken within him as he saw him slump lifelessly, as he had not in his lifetime before. The girl remained blissfully silent, innocent and uncomprehending of the situation.
He briefly pondered killing the girl. She hadn't cried at all since he'd come in here – he couldn't stand noisy brats. Perhaps that deserved some mercy over her brother? She was not a real danger to him, after all – the prophecy had specifically mentioned a he, not a female.
The baby looked solemnly up at him with little green eyes. They were the color of locusts, he noticed. The boy's hadn't been that color – they had been livelier, with a disgusting kindness to them. The child had eyes and features all her own, waiting for her true self to be revealed. He thought her lucky to be born as such. It had taken him many years to strip away the resemblance to his disgraceful parentage.
For several moments, the two observed each other. For a half a second, he thought he might be slightly unnerved – then he realized that the matrons at the orphanage must have felt the same way about him. He had never cried as a child. Why should he feel frightened of a child he knew was magical, that he knew to be special? He was better than those filthy Muggles.
Hesitantly, he put out his hands, reached under the infants arms, and picked her up. She kicked and frowned, but didn't yell. Commendable – most others would have certainly bawled their little lungs out at a stranger picking them up.
He looked at the blanket in the crib. Harry and Rose, it said proudly in gold embroidery. Rose. He openly scoffed. Such a common name – so light and innocent. Of course the Potters would call their daughter a flower. It was almost as bad as Tom, or even Harry. Disgusting.
He didn't quite know why at the time, but he took her with him, after changing the pastel pink color of her onesie (the name made him gag, and he instantly decided that he would think of it as her clothes) into a shade of mint green. He Apparated out, the baby girl tucked under one arm.
When he arrived back at the Slytherin manor (which, it turned out, he had successfully discovered in this universe) he deposited her in the care of one of the house elves – Floppy, he believed his name was – and instructed him to prepare a room for her, and to learn how to take care of an infant. He wasn't going to be feeding the brat himself, that was for sure.
The elf bowed, and then, levitating the infant, asked if Miss had a name.
“Rosaline,” the Dark Lord answered. Then he realized that she needed a last name. Potter was hardly an option, so.... “Rosaline Slytherin,” he added.
The elf bowed again, and went up the stairs, taking the baby with him. The Dark Lord's eyes followed him until he rounded the upstairs corridor.
And then Lord Voldemort wondered just what had possessed him to do what he did in the past hour.
To many, the idea of the Dark Lord adopting a child was ludicrous. Anyone else who suggested it would have been thought insane.
And yet, even as they went on to win the war and take over in the coming months, it seemed that ice rinks were opening up in Hell.
Bellatrix Lestrange cooed over the infant as she lay kicking in her silver cradle; any chance to cozy up to the Dark Lord was great by her standards. The Lestrange brothers themselves knew not what to think of the brat; they tended to pretend she didn't exist. Fenrir Greyback was kept out of her presence entirely; Severus Snape thought the whole thing very strange, but chose not to pry, and simply grieved for Lily Potter in silence. Narcissa and Lucius Malfoy asked Lord Voldemort (politely, of course) if perhaps Rosaline and their son Draco might play together; the Dark Lord declined (with equal politeness). Barty Crouch Jr eagerly asked if he might have the honor of teaching the Dark Lord's new daughter when she was older; he had replied that he would think about it.
Everyone lesser in the Dark Lord's regard knew little about the baby who they all supposed must be Lord Voldemort's pride and joy.
And not a single one of them dared to ask where she came from.
End Chapter I