Project Sekai is a multimedia project developed by SEGA and Colorful Palette, featuring virtual singers from the Vocaloid franchise. It combines rhythm games, music, and storytelling, allowing players to interact with characters and create their own music experiences. The project includes a mobile game called Project Sekai: Colorful Stage! feat. Hatsune Miku, where players can enjoy various songs and participate in live performances. It also features original characters alongside popular Vocaloid icons like Hatsune Miku, Kagamine Rin, and Kagamine Len, enhancing the overall experience for fans of the genre.