With its millions of users, "U" has become a well-known social media platform where one can reinvent themselves with a virtual persona. One of its latest members, Belle, a stunning singer, has captured the attention of the masses with her enchanting melodies. However, the mystery surrounding the true identity of the beautiful songstress, in a world where avatars hide everyone's true selves, piques the curiosity of many. Suzu Naito, a timid girl from the countryside, has been unable to sing since a traumatic event in her past led to breakdowns and illness. Yet, upon joining U, Suzu is able to once again find her voice. Going by the name "Belle," her vocals quickly go viral receiving love and hate in equal measure. Meanwhile, rumors abound of a malevolent entity on U, referred to only as "The Dragon." Following a chance encounter during her concert, Belle discovers that he may not be as malicious as the stories suggest. Suzu must now confront fame, identity, and opening her heart, both online and off, as she navigates a world of uncertainty.