大島優子
In early 2012, following scandals in which members Natsumi Hirajima and Rumi Yonezawa resigned from AKB48, Matsui was added to AKB48 as a temporary concurrent member to fill in one of the vacant positions. She later made her debut performance at AKB48 Theater on June 1. On September 18, Matsui was announced to be one of the center performers for AKB48's 28th single "Uza" with Yuko Oshima, and performed the song for the first time at the group's rock-paper-scissors tournament.