Why the heroine became the villainess?

PROLOGUE

Knock. knock.

"Lady Beatrice"

With the sounds of knocking and calling behind the door, she opened her eyes. An unfamiliar ceiling came to her view. Her brows frowned. She hurriedly looked around the place while still on the bed. It was a large room with wide glassy window and passing through, a terrace. The bedroom is too big to be compared for a master bedroom size. Overall, the place is emitting a royalty aura as it somehow left historic details to its interior and furniture. The pink color of the pillow, curtains, and blanket is befitting for a princess.

"Ugh! my head.", Roanne held her both temples. She felt her brain was cracking.

"Lady Beatrice.", a woman voice came behind the doors.

Unintentionally due to her sudden headache, she loudly questioned the woman behind the doors. "Beatrice? Who is Beatrice?"

"Lady Beatrice. May I come in? Your maid, Marielle.", the woman said not answering to her prior question.

"Come in.", Roanne answered back.

Then, the doors opened and a woman came in wearing a typical cosplay maid costume, black dress with white apron. "Good morning, Lady Beatrice.", Marielle bowed.

Still holding her temples, Roanne asked her. "Who is you calling Beatrice and where am I?"

"..."

The maid, Marielle, perplexedly gazed at Roanne. "Is there something wrong, Lady Beatrice?"

"You are calling me, Lady Beatrice?"

"Yes, because you are Lady Beatrice.", Marielle hesitantly answered her question. Now that Roanne is looking at the said maid, she noticed that her hands are shaking and her body seemed to be stiffened. "Lady Beatrice Delavine Croix.", as Marielle continued.

"Lady Beatrice Delavine Croix?", as Roanne asked in her head. She slowly examined her body. She noticed her hair is long that would length up to her hips, and with silvery color strands. She was dumbfounded. She tried to touch her face skin. She doesn't feel any wrinkles. Her arms were slender white and smooth. "I am not old so why do I have this silvery hair."

"Lady Beatrice?", spoke to Roanne with shaking hands.

"Can you give me a mirror? Please."

Marielle went out to the room and came back with what Roanne ordered her to bring. She handed it gently to Roanne as if her life depended on it.

Looking at the mirror, in her line of sight, a beautiful woman with mystery dark blue-sky color eyes and silvery colored hair came into view. She slowly blinks her eyes making sure that it is really her who was reflecting in the mirror. Smile. Pout. Blinks again. Smile. Blinks again.

Marielle, who was near, found the lady strange.

As Roanne gazed at the maid after examining herself in the mirror. "Marielle, right?"

"Yes, yes my lady?", Marielle stiffened.

"Will you do your usual morning routine?", Roanne thought it is best that she would be left alone for now for her to grasp the whole situation that she is presently in.

"Usual— Ah Yes, I will prepare your bath, my Lady.", Marielle hurriedly stepped outside the room.

When the maid is already out of Roanne's sight, she consciously embraced herself, curling up on the bed. Her confused mind worsening the headache she felt after waking up. Internalizing, all the memories started to flash in her mind.