Hitori "Bocchi-chan" Gotoh is a lonely high school girl whose heart lies in her guitar. One day, she meets Nijika Ijichi and joins 'Kessoku Band'. After that, her daily life starts to change little by little.

Hitori Gotoh, "Bocchi-chan," is a girl who's so introverted and shy around people that she'd always start her conversations with "Ah..." During her middle school years, she started playing the guitar, wanting to join a band because she thought it could be an opportunity for even someone shy like her to also shine. 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 to the internet under the name "Guitar Hero" and fantasized 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. She was really close to becoming a shut-in, but one day, Nijika Ijichi, the drummer in Kessoku Band, reached out to her. And because of that, her everyday life started to change little by little.—Crunchyroll

Hitori Gotoh, a shy, awkward, and lonely high school student dreams of being in a band despite her doubts and worries, but when she is recruited to be the guitarist of a group looking to make it big, she realises her dream may be able to be fulfilled and come true.—themoviedb