Chiyomiya Harem no Torikae Shoki Hime

A girl named Anastasia, who enjoys reading, is taken to a palace known as the Palace of a Thousand Nights, where a harem of one thousand women resides. She is brought in as a servant. Her brother, who works as a scribe, tries to keep her true identity as a woman a secret. As a result, Anastasia takes her brother's place and becomes the palace's scribe instead.