Z4-B1

 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
None currently

Former Members

 * Shukuzu Nuko (酒屑ぬこ) (Founding member)
 * Tsukino Mizuki (月野みずき) (Founding member)
 * Asahina Rin (朝比奈凛) (Founding member)
 * Ueda Moca (上田望夏) (Founding member)
 * Yuzuki Misato (雪月みさと) (Founding member)