後宮の男装妃 〜謎解き娘は皇帝のお気に入り〜, The Cross-Dressing Consort of the Harem ~The Mystery-Solving Girl is the Emperor's Favorite~, Koukyuu no Dansouhi ~Nazotoki Musume wa Koutei no Okiniiri~

"Suiran, a strong-willed girl raised in the mountains, is chosen to enter the imperial harem as one of the emperor's eighteen consorts. Soon after, the handsome emperor Yoshisou commands her to investigate the identity of a mysterious 'phantom' haunting the harem…!? A gender-reversed, mystery-solving Chinese palace fantasy!"