Dullahan

A weird-looking female knight that appeared in Hein's Castle, located in a world far away. She cradles her head with her arm, while riding a headless horse. She is a manifestation of a warrior's soul who have died with regret on the battlefield, and not a ghost. Why she roams the halls of Hein's Castle is unknown, but she will attack any human she finds there without mercy, so there is no other choice but to take up arms when encountering her.