原因は自分にある。 (GNJB)

原因は自分にある。, romanised as Genin wa Jibun ni Aru and shortened to GNJB or Genjibu, is a seven member Japanese vocal and dance group within the EBiDAN family at Stardust Promotion. It began in 2018 under the name BATTLE STREET and took its present name on 7 July 2019, with the change announced that August.

The debut single, sharing the group name, was released on 9 October 2019. The members are Takato Okura, Kosaku Koizumi, Masaya Sakuragi, Ryota Nagano, Jun Muto, Kazuto Mokudai and Kaname Yoshizawa. Masaya Sakuragi also works as an actor and holds a profile of his own in this catalogue.

The group’s sound is described as blending vocaloid influence, J-pop, Japanese rock and hip hop. The fandom name is 観測者, Kansokusha, meaning observer.

原因は自分にある。 has built a steady album catalogue with Stardust Records, releasing 多世界解釈 in January 2021, 虚像と実像 in December 2021, 無限の終わり in January 2023 and 仮定法のあなたへ in March 2024. The writing leans literary and philosophical, and the group has worked with Ayase of YOASOBI while drawing on vocaloid, J-pop, Japanese rock and hip hop.

Live work is organised around the numbered げんじぶ空間 series alongside regular touring. The EP 文藝解体新書 arrived on 11 March 2026, and its title track ニヒリズムプリズム gathered 1.8 million views in its first week. During the spring tour dates at Omiya Sonic City on 17 and 18 March 2026 the group announced its first arena tour, ARENA TOUR 2026 仮ノ現, which played Kobe World Memorial Hall in late June 2026 and Ariake Arena in Tokyo in early July.