Harry Potter isn't mine, however OC is.
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It was a cold autumn evening, when the Lestranges were caught and arrested for their crimes, especially the torture of Longbottoms. As they were caught on the crime scene, the trial was fairly short, just enough to document their crimes. The same evening they were taken to the Azkaban.
There were few who knew of Lyra Bellatrix Black, the daughter to the mad murderess Bellatrix Lestrange, nee Black. It was one of them who decided that the child needed to grow up in the Muggle world so that she wouldn't have her childhood destroyed by her mother's reputation. It was a pity that person hadn't thought to put her with the Tonks family and let her grow alone without a family for an anchor.
The Londoner's orphanage wasn't overly big or small, just average. Each room was shared by two or three children. The caretaker, widow Amanda Styll, was boring and slightly dim-witted woman. She had no clue of highly unusual things happening just under her nose. All were caused by young girl with black hair and silver eyes, and exceptional height of 5 feet and 2 inches.
Lyra Bellatrix Black had always known that she wouldn't live in an orphanage till her adolescence. She had been making plans ever since she learned of her magic.
Lyra still remembered just how surprised were her fellow orphans when she, proud yet distant Black, started to offer her cleaning services for a pay. Of course, most of the time she used her magic to clean, mostly when no one saw her doing it. The pay wasn't too large, only 5 pounds per flat cleaned, but as she managed to find time to clean about 50 flats per month, Lyra collected a decent amount of around 13 400 pounds. She collected the money for her future needs.
Lyra Bellatrix Black had never had a friend, it wasn't that she was being bullied, because she was too intimidating for bullies, it wasn't that she herself was a bully, she wasn't, it was simply her proud and cunning behavior, unknowingly inherited from the Black family. Because of this, each day after school she buried herself in library books, especially ones talking of business management, human psychology, political and casual ways of manipulation as well as meditation. She read meditation ones only because of possible insight into controlling her magic. She finally succeeded on her 9th birthday as during her meditation in her mind she saw a ball of her magic. It's color was bright silver, just like Lyra's eyes. Ever since this discovery Lyra Black dedicated most of free time to practice with her magic.
It was a few months after her eleventh birthday when she received a yellowed letter.
"Lyra, come here, now!" shouted Mrs. Styll up the staircase. The girl wondered what could have happened. She really hoped it wasn't someone wishing to adopt a child, because in that case she would have to convince them to choose someone else.
When Lyra Black came down the stairs, she saw a tall dark haired woman standing next to the caretaker. She seemed professional and very unlike a wannabe mother.
"Miss Black, this is Professor Aurora Sinistra. She says she is from some school and wants to speak with you." said caretaker already going back into her office on the first floor.
"Miss Black, you're a witch." immediately said a Professor and with these words Lyra felt a bone-deep certainty that it was the truth.