Oyasumi Sekai

 (おやすみセカイ) is an idol group that debuted in February 2017.

Current Members

 * Kawai Meu (可愛めう; ) (Joined July 2020; leaving October 21, 2023)
 * Mikanagi Ruru (御巫るる; ) (Joined November 2021; leaving October 21, 2023)
 * Konose Noa (恋瀬のあ; ) (Joined December 2022; leaving October 21, 2023)
 * Ebichou Mai (蝦煠まい; ) (Joined June 2023; leaving October 21, 2023)

Former Members

 * Amatsuka Milky (天使みるきぃ; ) (Founding member; graduated September 2017)
 * Shirosaki Mayu (白咲まゆ; ) (Founding member; graduated September 2017)
 * Kamiya Jurina (神谷じゅりな; ) (Founding member; graduated February 2018)
 * Rikapi (りかぴ; ) (Founding member; graduated February 2018)
 * Raimu Miu (来夢みう; ) (Joined October 2017; graduated February 2018)
 * Sakuragawa Mika (桜川みか; ) (Joined February 2018; left June 2018)
 * Emo (えも; ) (Joined February 2018; graduated August 2018)
 * Kino Ririka (城乃りりか; ) (Joined February 2018; graduated August 8, 2018)
 * Kurumizawa Yuzu (胡桃澤ゆず) (Joined July 2018; left pre-debut August 21, 2018)
 * Kisaragi Moe (如月もえ; ) (Joined February 2018; fired October 10, 2018)
 * Shiina Mio (椎名美桜; ) (Joined July 2018; graduated October 2018)
 * Chida Umino (千田羽海乃; ) (Joined November 2018; graduated March 2019)
 * Kusunoki Reina (楠木れいな; ) (Joined February 2018; graduated April 30, 2019)
 * Torase Miyako (虎瀬美也子; ) (Joined November 2018; graduated April 30, 2019)
 * Minagawa Yuuka (皆川優香; ) (Joined November 2018; graduated April 30, 2019)
 * Hoshino Miru (星乃美流; ) (Joined April 2019; left pre-debut May 4, 2019)
 * Howata Kotone (穂綿ことね; ) (Joined April 2019; left February 8, 2020)
 * Kurosaki Sakura (黒崎さくら; ) (Joined April 2019; left February 8, 2020)
 * Mashiro Rima (真城りま; ) (Joined April 2019; left February 8, 2020)
 * Akakuri Seina (明栗聖奈; ) (Joined April 2019; left February 8, 2020)
 * Sakura Momo (桜もも; ) (Joined February 2020; graduated April 27, 2020)
 * Nakamoto Seina (中本星七; ) (Joined February 2020; graduated April 27, 2020)
 * Ogawa Nene (小川寧々; ) (Joined February 2020; left May 2020?)
 * Kamijou Rin (上條りん; ) (Joined February 2020; left May 2020?)
 * Ichinose Riru (一ノ瀬りる) (Joined July 2020; left September 2020?)
 * Himeno Fuyu (姫野ふゆ; ) (Joined July 2020; left December 31, 2020)
 * Minami Sayaka (美南さやか; ) (Joined November 2020; left March 24, 2021)
 * Nowan Moe (雪餅羽もえ; ) (Joined November 2020; graduated August 5, 2021)
 * Amatsuka Ruria (天使瑠璃亜; ) (Joined February 2021; hiatus since August 6, 2021; left September 25, 2021)
 * Kou (小雨; ) (Joined February 2021; graduated March 5, 2022)
 * Fujisaki Ria (藤咲りあ; ) (Joined July 2020; graduated April 21, 2022)
 * Medeaizuki Neru (愛逢月ねる; ) (Joined November 2021; graduated April 21, 2022)
 * Hoshijima Mana (星嶋まな; ) (Joined January 2021; graduated October 28, 2022)
 * Kokona Mogana (心那もがな; ) (Joined February 2021; graduated October 28, 2022)
 * Usagi Yuyu (兎木ゆぅゆ; ) (Joined December 2022; graduated May 11, 2023)

EPs

 * [2019.09.28] Oyasumi Dekinai Gozen 2-ji! (おやすみできない午前2時!)