The 2nin3kyaku Project (二人三脚プロジェクト pronounced "Nininsankyaku Project" lit. Three-legged Race Project) is an idol group project that serves as the junior group to 22/7 in 22/7 Ongaku no Jikan. The group consists of 11 members, each assigned to study under a respective 22/7 member.
All members attend Rokubanchou Academy.
- Kasuka Akutsu - Understudy of Reika Sato
- Maki Igarashi - Understudy of Miu Takigawa
- Kyoko Kurose - Understudy of Ayaka Tachikawa
- Momoji Shiina - Understudy of Mikami Kamiki
- Shion Nanasaki - Understudy of Sakura Fujima
- Tomoe Hasunuma - Understudy of Miyako Kono
- Kokoa Misaki - Understudy of Akane Maruyama
- Haruna Muranaka - Understudy of Tsubomi Hiiragi
- Suzune Mori - Understudy of Yuki Tojo
- Hikari Yashiro - Understudy of Nicole Saito
- Runa Wakaizumi - Understudy of Jun Toda
From April 11 to May 8, 2021, fans voted on selecting 11 out of 30 candidates to become juniors to the current 22/7 members within the game Ongaku no Jikan.
On May 23, the members that made it through were announced, as well as their names and their seiyuu.
On June 2, the pairings were decided through random selection by the 22/7 members themselves. This was done by picking blank envelopes containing the profile of a 2nin3kyaku member inside.