A/N: Okay. So Bellatrix is one of my favorite HP characters. And I've always felt as though there's much more to her than comes across in the books. Thus, this idea was born.
Growing up, Narcissa and Andromeda were always the close ones. Bellatrix was older and looked like a porcelain doll with her pale flesh and long black hair. A porcelain doll everyone was afraid to break.
Andromeda was the middle child. The studious one. She was quiet, cold and contemplating. She always wanted to be just like her sister, combing her hair and practicing her expressions in the mirror for hours every day until one day she didn't. Until she abandoned them all and left the Black family forever. Until she became a coward. Andromeda ended up a little bit too much like Bellatrix. She observed her too closely- closer than anyone had and ever did- and picked up on the way she clenched her fork in her hand whenever their father spoke about politics and Albus Dumbledore.
Once Andromeda left Bellatrix knew she would never be able to. She gave up her exotic fantasies of running away, starting a new life. She married Rodolphus and let Andromeda be the traitor.
Narcissa never liked Bellatrix. She fell in love her second year with the handsome prefect and never looked back. She loved Draco and Lucius and she killed Bellatrix for them. Her Bella.
Bellatrix knew her sisters were traitors. And she knew that she never could be.
Bellatrix was terrified. She was terrified she wouldn't be put in Slytherin.
She worried that once the sorting hat found out her favorite thing to do was read, it'd yell out 'Ravenclaw!' and her life would be over. Over.
She'd read Hogwarts, A History. She knew that once the hat spoke, there'd be no turning back.
But she could never prepare herself for what the hat whispered.
"You would do well in Hufflepuff, my dear. A loyal heart, that is for sure."
Bellatrix panicked. Hufflepuff? No one was in Hufflepuff. Hufflepuffs never did anything. It would be better to be put in Gryffindor!
"Is that what you want, my dear? To be put in Gryffindor?"
No! No. I want to be like everyone else. I want to be in Slytherin.
"Are you certain? This is a big decision. There is no turning back.
Bellatrix squeezed her eyes shut. I'm sure. But will it listen? Will it care?
"I care. It's important."
"Slytherin!" The hat yelled.
Bellatrix Black put on a cold expression and walked over to the proper table.
The hat did that to everyone, right? She did belong here, right?
Bellatrix never liked Lucius. He always seemed slimy, like her was about to run away from something. He and Cissy made a fantastic pair.
People never said that about her and Rodolphus.
A/N: Okay. So I am in desperate need of a beta reader for this piece. So if you liked it and have some ideas, message me. Or if you absolutely hated it and thought 'What? I could write something ten times as good!', message me and tell me what to change. Or leave a comment. Clearly I cannot control your actions.