More details will be released at a later date.
FIRST AND FOURTEENTH VOLUMES:
VIZ Media publishes the manga in English and describes it as:
Richard's father, the patriarch of the House of York, is poised to become king of medieval England during the bloody Wars of the Roses. But just as success is imminent, he is abruptly cut down. Plunged into despair, Richard acts out in revenge and must face a powerful and beautiful new enemy.