An Extra Character Became A Villainess AECBAV

Sypnosis/Prologue
She was born to a half-witch mother and an archmage father therefore she was blessed with a lot of mana In her body.

When she was 8 years old, her family was killed by unknown people and she was the only one who survived, she was enraged by her parents' death so she decided to take revenge on them.
"Mom, Dad, Sister. I will avenge your death no matter what." One day while she was practicing magic and swords, she discovered that she had the most powerful magic, however even though she had a lot of mana, she would always get exhausted when using her magical power. And to live without starving she became the youngest assassin, the people of the Lavastian empire ordered her to kill all the traitors, and steal 5 gold every week. And one day the duke and the duchess Flowell changed her life from stealing and killing when they decided to adopt her as their daughter because the duchess could not bear a child.
After 6 years with her new family, the happy family split up.
They died In a carriage accident but their bodies were not identified, and the emperor ordered them to investigate their deaths. Within a few weeks, there was news that they had been killed by bandits. As her rage resurfaced at the news of her family's death and because of the one who killed them, she decided to take revenge on them.
After two months, She went back to killing people and was called the "Dark killer" in the Cevallos empire because she was always wearing a black mask and a black cloak whenever she was on a mission.
While she's finding the murderer of her new family and her original family, she was surrounded by the love of the male leads.
" As I thought, this world I was living In was a world fantasy romance novel."
when she met one of the male leads she suddenly remembers her previous life in the novel that she read on her past life before she was reincarnated.
And the fact that she only remembers her past life when she met one of the male leads is the start of the novel called 'Flattering Blossom Fantasy Romance'.

Alternative titles/
"I'm just a extra character, so why are these male leads are obsessed with someone like me?!"

"An extra character became a villainess"

My sypnosis isn't official yet, i still find some things to shortened it.