Hitori 'Bocchi' Gotoh is an introverted girl. During middle school, she took up the guitar, wanting to join a band. But because she had no friends, she ended up practicing guitar for six hours every day all by herself. After becoming a skilled guitar player, she uploaded videos of herself playing the guitar under the name 'Guitar Hero' and fantasised about performing at her school's cultural festival concert. But not only could she not find any bandmates, before she knew it, she was in high school and still wasn't able to make a single friend! One day, Nijika Ijichi, drummer of Kessoku Band, reached out to her. And because of that, her everyday life begins to change little by little..