I Became My Sister to Avenge Her

The kingdom holds that twins are an ill omen, and an imperial decree lays down what is to be done about them. In the household of the Minister of War that meant the younger of two girls, Lorraine, was shut in a hut on the hill behind the house and kept in chains. The only person who came to her was her twin, Winifred. Winifred taught herself to open the locks, and as the two of them grew up they swapped places from time to time. Winifred was the one warm thing in Lorraine's life, and Lorraine's nature changed under her. The Empress Dowager arranged a marriage between Winifred and the heir of Prince Jance. Winifred accepted it because it gave her a way to get her sister out, and she promised to come for Lorraine on her wedding night. On that night Winifred came to the hut covered in blood, undid Lorraine's chains and died. Her body carried a great many marks of abuse. Lorraine cut herself to copy the wounds and went into Prince Jance's mansion in her sister's place. She keeps her identity hidden there while she looks into what happened to Winifred, and what she begins to turn up is a secret kept by the house that ties back to her sister's death.