Nakanai Tori no Kaeru Ki wa

In the small kingdom of Reven, a new king's coronation leads to a sudden economic collapse. Because of this, young Lydia cannot afford her sickly mother's medicine; but unexpectedly, a man kindly purchases it for her. Determined to repay the favor despite her lack of experience, Lydia becomes a maid for her benefactor: Lord Evert Drake, a former politician surrounded by foul rumors.

While accompanying her master to town, Lydia rescues a mute girl named Shiki from being sold off as a slave. Shiki, in turn, protects Lord Evert from an assassination attempt. Moved by Lydia's kindness, Shiki wishes to stay with her and is soon appointed as another one of Lord Evert's maids.

One day, Lydia overhears an unknown female voice inside Lord Evert's room. As Lord Evert was not expecting any guests, Lydia's suspicions immediately fall on Shiki—the only girl she has never heard speak. Puzzled by the incident, Lydia decides to further investigate the matter, hoping to uncover the mystery behind the voice and its connection to Lord Evert's surfacing enigmatic past.