Wake Up, Girls! was an idol unit active from 2014 to 2019 whose leader was none other than Yoshino Aoyama, voice of Hitori “Bocchi” Gotou in Bocchi the Rock. In this performance of the opening theme from Restaurant to Another World, originally a collaboration with Mayn, she’s the one singing the very first line, with the light blue ribbon.
Far from the absolute nobody before Bocchi the Rock she’s sometimes painted as (also by her own presentation), she had before already led this unit throughout the years, culminating in this final concert in a brimful Saitama Super Arena in front of about 35,000 people (full concert playlist) that wowed her senpais Rie Takahashi and Reina Ueda.
During the unit’s active years, she also voiced the character based on herself in various accompanying anime productions.
After the unit disbanded after this concert, the only other member that continued to be significantly active in the idol and/or anime space AFAIK is Minami Tanaka, who e.g. went on to become part of Franchouchou in Zombieland Saga.