Sela Seo is a high school girl who has a complex about her deep voice. Ever since she was teased about her voice in middle school, she has been unable to say what she thinks out loud and has been unable to fit in with her class. In Sela's class was another outcast, Tatsuto Narukami, a boy who always wore headphones. She assumed he was just another “loner” like herself, but when she saw him singing behind the school building during lunch break, her feelings changed.