Z4-D1

 is a group within Zero Project. The theme of the group is royalty.

The first line-up was announced on November 20, 2021.

They made their stage debut on November 21, 2021 @Ebisu Garden Hall.

Current Members

 * Ichiba Uno (市葉羽乃) (Founding member)
 * Mori-chan (もりちゃん) (Founding member)
 * Luna (月) (Founding member)
 * Kurumisawa Narumi (胡桃沢成未) (Founding member)