Fushigiboshi no Futagohime

Seven royal families reign over each of the seven kingdoms of Wonder, prospering inside the planet for many years. Ohisama no Megumi (the sun's blessing) is beginning to die, and, if it disappears, all of the planet will be covered in darkness. Twin princesses Fine and Rein receive a secret mission from Princess Grace to use the power of the Prominence and rescue the Ohisama no Megumi. Meanwhile, they attend several Princess Parties and get to know the other princesses of Wonder.