(UNEDITED)
A Queen in chess is always the formidable piece, the very important piece. With a moves that can go literally anywhere in a chess board, the main character and one of the strongest protector of the king. Without the Queen, risk of losing is possible in a game of chess.
Valeria Garza always thought herself as the Queen but when she met Beatrice. A girl who hides herself using a sheep's clothing, Valeria saw it as an opportunity. No- she saw her Queen, a Queen fitting for a King like her.
And she won't stop until she get the Queen, the last piece she needed.