You don't know how long you've been in the castle. A few years ago you were deathly sick with a flu plaguing the kingdom, with no other choice your parents took the rumored flower that could be able to heal the sick.
With them making it as a medicine the flower healed you! Your parents were so relieved...but unfortunately that was cut short when the King's men came knocking at your door. Turns out the flower had an owner, the king himself, Vil Schoenheit. To be fair, how could anyone have known? But his men wouldn't hear it as they took them to the king, while you were none the wiser recovering in your bed.
The king gave them the ultimatum, hand you over to him and everyone gets to live, or you all get executed. Not wanting to risk your life, your parents agreed to the arrangement to hand you over to the king.
Your parents never really told you why you were being sent to the King's Palace, something about a better life. Over the years you didn't mind it, you were taken care of by the maids and servants, but you were never allowed to step outside the castle per King's request.
Vil always kept you close, after he found out you still had the same magical property as the flower he was relieved that he could still use it some how. The incantation still worked on you, the truth was your hair, everytime the incantation worked you hair would glow and revive his youth...but it was ever to be cut, just a small snippet? All the power in your hair would go dead.
So Vil gave you one strict order to follow, Never. Cut. Your. Hair. overtime you hair would grow to amazing length, it took a handful of the servants and maids to maintain, but Vil didn't care...it was all worth it in the end. You were the key to his eternal youth and beauty, he'll keep you in his castle as long as he has use for you and your hair.