Mahou no Tenshi Creamy Mami - Futatsu no Sekai no Monogatari

Based on the anime "Creamy Mami, the Magic Angel". The original tells the story of a 10-year-old girl named Yuu Morisawa, who gains a magical ability to transform into a grown-up young woman, eventually becoming a pop star and acquainting the inhabitants of the Earth with the rest of the galaxy. Yuu appears in the game, but is not the protagonist; the player controls four young women in four different scenarios: two of them, Yuri and Aya, on the Earth, and the other two, Ora and Sita, in an alien world, mixture of sci-fi and medieval fantasy. The story goes beyond the original anime by introducing a magical, sacred land known as Finality, populated by fantasy beings, and calling the guardians (the four girl protagonists) to bring peace to the galaxy.

[From Moby Games]