To Share A Soul

Summary: When you have lived your whole life with only one other you trust, one who is your twin, who might well be half of you, would you not start to share a soul?

Notes: This is a HP AU fic, and part of an on-going thing I'm working on. This will be updated out of order, and I'll note as other parts of this AU come up where they fall in this universe's timeline. The spells in this are utterly invented by me, and basically translate to "Soul outside", "Soul inside" and "Bind me" or "hold me". Please also note this has been translated into Russian, by the wonderful VassaR of AO3 and FicBook, and can be read at ficbook, the fic-code is 4545113 [I can't put the actual link in because THANKS FANFICDOTNET]. If you PM me I can direct you to it specifically.

Warnings: Blood, Gore (sort of), Horcruxes, Codependency

Pietro holds up the knife, silver-steel blade shining under the light of the waning moon. It glows between them, point at a level with Wanda's chin, but several inches away, evenly betwixt them both.

"Are you ready?" she asks, and her voice is a breath. Pietro nods. They have already divided their souls. Killing arsonists with arson is just as effective at dividing souls as the Avada, but they used that as well, together, when two tried to escape the climbing flames. They can feel the torn fragments of themselves, fluttering just beneath their hearts. The moon, waning as it is, tugs on the fragments, prepared as they have, with meditation and focus, to decant them from their bodies into Horcruxes.

Wanda turns, and bares her back to her brother.

The knife cuts a simple line down her back, and blood beads in the fine scarlet line of it. It trickles down, down and down, and Pietro's wand darts rapidly to catch it all, and place it in the bowl they brought for this purpose.

The potion in it is a swirling mass of colour. Sometimes deep brown, sometimes virulently yellow, sometimes acid-green, and sometimes fleshy scarlet, like dead flesh. It contains the hearts of the ones they killed, and the bones of fish, ground down fine. It contains tears of grief and of joy, both collected within minutes of each other, and it contains a pint of honey, fifteen flowers, thirteen acorns, seven fertilised chicken's eggs and three dog's eyes. Now, it also contains Wanda's blood.

Pietro does not have time to seal the slice with dittany before Wanda turns, and takes the knife from him.

"Your turn," she murmurs. Pietro bares his back to his sister, and cannot quite hide the gasp of pain as the knife makes its way down his back, through his skin, from nape to mid-back. Wanda's quick spell catches his blood, and adds it to the bowl. Pietro eyes the now sickly-purple mess.

"Will it be enough?"

Wanda nods. "Living Horcruxes are different," she says, and dips her fingers in it. "Let me mark you?"

Pietro bows his head, and lets Wanda draw the potion, smelling of corpses and of roses, of manure and of sweetness, of sorrow and summer, and snow and joy, and petrichor and a desert onto his skin. The contrasts turn his stomach, and he almost heaves as he smells marsh and woodsmoke, blood and stone, metal and putrefaction. Wanda draws her fingers down his brow, from the centre of his forehead, down his nose, over his lips and down his chest. Scents rise, eggs and weeks old sweat, worn leather and horses, salt-mud and cotton candy. She marks the palms of his hands, the tops of his feet, the backs of his knees, and the point on his back, where spine meets hips, and they try to ignore the sickly sweet smells of life and death and decadence. The last of the mixture is spread over his eyelids, and around the curl of his ears, and smeared over lips top and bottom.

Then Pietro does the same to Wanda.

They stand, nose to nose, when it is done. They wear very little, and trust warming charms to keep them from shivering in the cool of the night. They raise their wands.

"Anima Externalis," They intone, and try not to lurch as they feel the fluttering ribbons of soul in their chests finally tear loose. The ribbon is scarlet from Wanda, as scarlet as her blood, as scarlet as her eyes in the fire they have to dispose of everything when they're done. It is bright, and it floats out of her chest, from between her breasts and just slightly to the right, like a tangled and torn piece of silk, flickering in the flames. It settles by her wand, just as Pietro's ribbon, blue, like watered silk, and flickering silver with each fluctuation it makes in the breeze, settles by his.

Their eyes meet, dark brown glowing with scarlet flames, to bright blue glowing with energy and magic. They need no words to ask their question, and dare not speak and ruin the magic. Ready? Their eyes ask, and they each incline their heads just a millimetre.

Their wands move forwards, away from their bodies, towards their twins'. Their wand-tips press to the line of sickly purple potion that runs over their sternums, and moves slightly to one side, over their hearts.

Their voices are twin breaths. "Anima Internalis."

The ribbons, glowing blue, and glowing scarlet, sink into the skin of their twin. They each relax as they feel it, feel their soul settle into place, and fill the gaps from taking out half their own souls. Wanda feels Pietro's blue coil, contentedly, around her remaining scarlet, feels her scarlet interweave itself with his blue. Pietro's head falls, calmly, peacefully, to her shoulder, as he feels his blue wrap around his sister's scarlet, and her scarlet interlink with his blue. Wanda's brow falls softly to his shoulder, and they both feel the tackiness of the potion as they shift slightly to raise their wands.

"Tenebit me," They cast, and feel the mortal grey pass over them, sink into their flesh, and anchor their souls in their twins body.

For a long while they are silent, feet bare in leaf litter, the sounds of the night creatures, of the wind, of their crackling fire, and the whisper of their breathing and nothing more.

It is Wanda who smiles, and huffs a laughing breath. "We might as well be one soul now," she says, "Given we have split ours evenly between ourselves."

End Notes: Reviews are much appreciated!