HARMONY OF MILLE-FEUILLE

First-year high school student, Uta Komaki. She has many weaknesses. But she loves to sing. Aiming for an ordinary youth, she tries to join the light music club as part of her high school debut—only to fail miserably due to her timid nature. In her despair, Uta encounters a form of music created solely by the human voice—a cappella. There, she finds a group of girls whose imperfect youth is woven together only through their harmonized voices. —Even without shining, it's still youth. (Source: Pony Canyon) — Description from AniList community (anilist.co).