Author of My Own Destiny

I possessed the body of Fiona the final villainess whose soul was sentenced to eternal suffering after her gruesome demise at the hands of the worlds hero
She was tortured by her own family just because she was an illegitimate child
And so arriving six years before the start of the novel I was sent to war at the age of thirteen Fortunately as the storys greatest villainess Fiona was a genius mage
I had to survive the monster invasion But now I couldnt be in the middle of a battlefield
Just before I ran out of breath I encountered the teenaged male lead
Why is he here
Well if the male lead dies here then the world will be destroyed So lets save him first