Yoake Mae yori Ruriiro na centers on Princess Feena Fam Earthlight from the Kingdom of Sphere on Earth's moon. It was decided that she was to live on Earth in a homestay with the family of the primary secretary to the president of the United Nations so as to get more knowledgeable of Earth in order to better prepare herself for her succession as the Kingdom of Sphere's next queen. The background of the story explains that humans landed on the moon long ago intending to create a new home for themselves called the Kingdom of Sphere. However, the relations between Earth and the Kingdom have worsened things and a war called the Oedipus war started. Once the war was over, it was decided that the city of Mitsurugasaki, where the story takes place, under the rule of the United Nations, be developed as the center of diplomacy with the Lunar Kingdom, which, currently, has closed its doors to the world.