Z5-A4

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

The first line-up was announced on July 8, 2021.

They made their stage debut on August 14, 2021 @KANDA SQUARE HALL.

The second line-up was announced on January 9, 2022 and debuted on January 15, 2022.

The third line-up was announced in March 2022.

The fourth line-up was announced on August 14, 2022.

Current Members

 * Ichinose Hoshi (一野瀬ほし; ) (Joined July 10, 2023)
 * Himeno Nana (姫野なな) (Joined August 2023)
 * Izumi Sumire (一澄純恋; ) (Joined July 10, 2023)

Former Members

 * Tsubaki Rion (椿りおん) (Founding member; Withdrew September 9, 2021 )
 * Aone Konoha (蒼音このは) (Founding member; Graduated November 12, 2021)
 * Ari-chan (ありちゃん) (Founding member; Graduated November 12, 2021)
 * Shukuzu Nuko (酒屑ぬこ) (Founding member; Graduated November 12, 2021)
 * Nanase Saaya (七瀬さあや) (Founding member; Graduated November 12, 2021)
 * Azuki Miyu (愛月心結) (Joined September 9, 2021 ; Graduated November 12, 2021)
 * Aoi Rui (蒼井ルイ) (Joined January 15, 2022)
 * Asakura Yuzuki (浅桜ゆづき) (Joined January 15, 2022)
 * Ikeda Haruki (池田遥希) (Joined January 15, 2022)
 * Nagahime Miku (長姫未來) (Joined January 15, 2022)
 * Yuki Sena (結城星奈) (Joined January 15, 2022)
 * Uyugu (うゆぐ) (Joined March 2022)
 * Kanraku Momo (柑楽モモ) (Joined March 2022)
 * Ten (天) (Joined March 2022)
 * Risa-nyan (りさにゃん) (Joined March 2022)
 * Kayano Izumi (茅野伊澄) (Joined March or April 2022)
 * Shiun Shino (紫雲しの) (Joined March or April 2022)
 * Shigeta Norika (重田紀果) (Joined March or April 2022)
 * Umesaki Risa (梅咲りさ) (Joined July 14, 2022)
 * Takase Miku (高瀬みく) (Joined July 14, 2022)
 * Mio (澪) (Joined July 2022)
 * Ayase Mayo (絢瀬まよ) (Joined August 14, 2022)
 * Takanashi Ranko (小鳥遊蘭子) (Joined July 14, 2022)
 * Hinata Kizuna (日向絆) (Joined August 14, 2022)
 * Mizuri (みずり) (Joined July 2022)
 * Isshiki Hiyori (一色陽頼; ) (Joined September 17, 2022)
 * Nono (ﾉﾉ; ) (Joined September 17, 2022)
 * Maonyan (まおにゃん; ) (Joined September 17, 2022)
 * Mikuriya Kureha (御厨紅遥; ) (Joined September 17, 2022)
 * Yozuki Ayu (夜月あゆ; ) (Joined October 25, 2022; Graduated November 29, 2022)
 * Aise Uru (逢瀬愛瑠) (Joined November 29, 2022)
 * Tokinaga Yukino (時永ゆきの) (Joined November 29, 2022)
 * ei (Joined November 29, 2022)
 * Mao (まお) (Joined November 29, 2022)
 * Mirei (美麗) (Joined December 28, 2022)
 * Oda Eri (織田えり) (Joined December 28, 2022)
 * Hashimoto Ruru (橋本るる; ) (Joined September 17, 2022; Re-joined December 28, 2022)
 * Hinokami Inori (日之上いのり; ) (Joined August 14, 2022; Re-joined December 28, 2022)
 * Yuyuko (ゆゆこ; ) (Joined January 14, 2023)
 * Anon (あのん; ) (Joined January 14, 2023)
 * On Reika (温翎禾; ) (Joined January 14, 2023)
 * Anzu (Joined March 6, 2023)
 * Sae (さえ) (Joined March 6, 2023)
 * Tahata Moeno (田畑萌音) (Joined November 29, 2022; Re-joined March 6, 2023)
 * Runa (月渚) (Joined March 6, 2023)
 * Sakuragi Mayu (桜木愛結) (Joined March 6, 2023)
 * Sui (穂) (Joined May 24, 2023)
 * Hanafu Sayuri (花房優里; ) (Joined January 14, 2023; Re-joined May 24, 2023)
 * Mizuse Kirara (水瀬姫羅良) (Joined July 10, 2023)
 * Yoshimura Mimi (吉村実美) (Joined July 10, 2023)