To train the one who would become the next empress, the eldest daughters from fives houses were gathered. House of Kou's maiden Reirin, who possessed a frail constitution and was beautiful as a butterfly, had the highest prospects to be selected. Out of jealousy, Keigetsu swaps their bodies. Reirin had suddenly become Keigetsu who was hated by those around her and called the "maiden court sewer rat." Now scorned by those who had previously treated her with kindness and with no one to believe her, she is placed in harsher circumstances compared to before, however... "I'm not short of breath and no longer feel faint... what a wonderfully healthy body! How enviable!" Having been accustomed to receiving the envy of those around her and constantly fighting face to face with death, she possessed an iron will. (Source: Shousetsuka ni Narou, translated)