Kojima passed AKB48's 14th generation auditions in 2012.[2] On July 20, Kojima was announced to be in a new sub-unit, Tentoumu Chu!, consisting of trainee members from AKB48 and its sister groups, together with Nana Okada, Miki Nishino, Ryoha Kitagawa, Nagisa Shibuya, Meru Tashima and Mio Tomonaga.[3] The sub-unit debuted on July 31. Kojima, Okada, and Nishino, also known as the Three Musketeers (三銃士, Sanjūshi), were promoted to AKB48's Team 4 on August 24.[3][4] She was selected to perform in a single title song for the first time for the song "Mae Shika Mukanee" (2014).[5] She was shuffled to Team K during AKB48's Daisosaku Matsuri.
On April 6, 2017, Kojima transferred talent agencies from AKS, which managed AKB48 and most of its members, to Sun Music Production.[6] She participated in the reality show Produce 48 in 2018, but was eliminated in episode 8.
On January 12, 2019, Kojima announced her graduation from AKB48 during a Team K concert at Tokyo Dome City Hall. On April 27, her graduation ceremony was held during the AKB48 Group Spring LIVE Festival in Yokohama Stadium. On May 12, her final performance was held at the AKB48 Theater. Her YouTube channel, the makochannel (まこちゃんねる), was launched shortly after.[7] She also announced the launch of her own clothing brand, haluhiroine (ハルヒロイン), which name is a combination of the Finnish word for "desire" (halu) and the English word "heroine".[8][2]
Personal life
On January 6, 2024, Kojima announced her marriage to actor Yuya Kido.[9]
^ abNews, Ameba (23 December 2021). "アイドルからプロデューサーへ。小嶋真子のセカンドキャリアの切り拓き方 | 話題" [From Idol to Producer: How Mako Kojima created her second career]. ABEMA TIMES. Archived from the original on 2022-11-05. Retrieved 2022-07-01. {{cite web}}: |last= has generic name (help)
^"AKB研究生7人組ユニット・てんとうむChu!お披露目 新曲熱唱" [AKB's seven-people trainee unit Tentoumu Chu!'s new song revealed] (in Japanese). Oricon. 2013-07-31. Archived from the original on 2014-02-22. Retrieved 2015-01-03.
