Hatsune Miku and KAITO were part of the Sekai from the beginning. The remaining virtual singers were added in the following events:
- On a Holy Night, with This Singing Voice: MEIKO
- Resounding Twilight Parade: Kagamine Rin
- The Tenma Household's Hinamatsuri: Megurine Luka
- A New Troupe Member Appears!: Kagamine Len