Because she had no choice in it, no choice in it at all
She's the most powerful magic user in the world, and she's a mother. She's created life, with her own blood and pain. Does this not make her a god in some way? She stares adoringly into blue eyes, cooing gently at her child, stringing her fingers through her soft curly blond hair. She smells sweet and new, and her heart swells up with love for this tiny little girl that she's made, her little Admirien. Addy.
She's burning, blind with the weight of her own melting flesh against her eyes. Blood erupts from her hands, a warm wetness against the uneven bumps of her new burns. She scrabbles against the wood of her house, her home, listening to the screams around her. One of her nails is torn off, splinters embedding themselves into the newly exposed flesh. She gags but keeps digging, the raw unprotected skin of her nailess finger digging against cement. She destroys her own body to destroy her own walls, all to find a tiny body, wrinkled with burns. The screams around her haven't stopped, but all she can do is stare at the tiny little head that was once hers, hair singed away. She finally closes her mouth and the shrieking stops, and the world is quiet except for the sound of crackling flames.
She stands in a room with a tiny casket. Other people are there.
The dusty tomes in front of her haven't been opened in literally a millennia. The archives of Mystacor have always had hidden sections, books locked from sight. She doesn't know what's weaker really, locking power away, or refusing to destroy it. Such half measures. Her hands still shake when she holds anything heavier than a bottle, so she sets the book down, flipping its pages easily. She'll find what she wants. Creating life is much more impressive than bringing life back, in her humble opinion.
They try to lock her away when they find out what she tried to do, and she burns them to death. She doesn't watch the flames, but she feels the heat against her back. She's banished, which hardly seems fair, she didn't even succeed. Their betrayal rings hollow against her insides, some strange emptiness in the shape of a worm, crawling around her guts and compressing them together. She is pulp, inside and out.
The Horde's lands are ravaged, dirty and ruined. She watches her hands and compares it to scorched soil.
She rises through the ranks quickly, which is unsurprising. Nobody's ever seen anything like her, this woman whose mouth gapes, teeth gleaming in a constant smile against her stretched out skin. Her voice, crawling and low, rumbling with damage from smoke inhalation. Intimidation goes a long way. And so does power, and nobody in a century has had the power she processes at her rickety, torn hands.
She puts on a mask, for fun. It's all very dramatic, this commander business.
They give her a tiny little baby as a ward. She has to retreat to her room, holding a small head in her skeleton hands, fingers playing in blond curls. Grey blue eyes looking back at her with trust. She did not make this one, but there is nothing in the world that will take it from her. Her little Adora. Unfortunately, they give her another "gift", a mistake, mewling pathetically at her. This is not her baby, its hair is dark and course, its eyes mismatched. It has ears and a tail, a beast with human hands. Despite her fondness for Adora, she has time to raise neither of them. The broodery cares for them, and she makes sure they know who should get food if there's a shortage. She's a busy woman, but she can do this.
Adora is whispering to her pet, rubbing soothing circles on it's back. She tells her not to bother, tells her to pay attention to her studies. Adora looks up at her with those grey-blue eyes and yells, tears dropping down her face. This is her friend. This is Catra. She is a she. Sometimes Adora has these mood swings were she doesn't act like how she knows she should, sweet and new, and hers. She feels a rush of horror, like she's missed a step, like the ground has fallen beneath her, and she swings her fist down, knocking Adora's head against the bed frame. Adora stops crying, but the little feral starts in her place, screaming fiercely. Here is someone she can hurt, without the feeling of vague guilt. She waits for her to come at her legs, violence blooming in her teeth.
It's easier, to punish Catra. Her daughter-her Adora, is too merciful sometimes. Her fragile little heart seems to burn to ashes at the sight of her friends pain. She hears screaming, but she doesn't stop, dragging it away by their ears.
She grows old and Adora grows mature, fighting and commanding and loving. Even in the Evil Horde, this weeping sore of pain and disgust, her little girl learns affection. She so often aims it at Catra, voice soft, hands gentle. She comforts, and laughs and hugs, and she stares instead at her, who raised her, with ungrateful eyes. There is admiration in those greys, but that wasn't the way it used to be long ago, when she was small and sweet and new. Catra though, is beginning to understand what it means to be punished in someone's stead. Her hands are a little less gentle against Adora's skin, thin pupils equally bitter as affectionate. Mismatched. Isn't that useful, she thinks as Adora combs through Catra's hair. It's anger is small, but she adds tinder until it erupts into flame. And she waits for it to kill.
She's trying to kill the parasite, the mewling little bundle that arrived at her door all those years ago (With Adora, Adora whose sweeter now, and old and no longer hers) but it fights back, dodging nimbly, claws slashing through malformed skin. Its hissing at her, voice rough from the time she gave it nightmares for a weak. You thought you were punishing me all these years? It yells, full of poison and fire and smoke, filled up with toxin and heavy. The answer is no, of course, because she was always an it, always insignificant, it was not Catra, and you can't punish something without a name. I bought Adora a pet, she wants to say, and it made her smarten up when I kicked it. But she doesn't, because it defeats her, burns her away, clearing the soil, the rot. Finally the fire stops burning, and finally the screaming stops. She is pulp now, without the shell, weak against the ground. She dies, flickering like a candle drowning in it's own wax.