Suzu is a 17-year-old high school girl who lives in the countryside of Kochi Prefecture in Shikoku, one of Japan’s four main islands. When she was a young child, her mother died in an accident, leaving her father to raise her by himself.

To Suzu, singing with her mother was the greatest thing in the world, but ever since her death, she hasn’t been able to sing a single note.

Somewhere along the line, she drifts apart from her father and closes her heart to the real world. Writing songs is the only thing keeping her going, until one day she casually decides to create an avatar she names Belle in the virtual world of U—an online space where a community of more than 5 billion users gather.

In the virtual world of U, Suzu can be another version of herself in another reality where everyone is connected.

In U, Suzu is able to sing again for the first time and her passion reignites. She starts performing her original songs and before long, she gains popularity worldwide.

However, before she has a chance to make sense of this newfound popularity, with a great roar, a mysterious entity suddenly appears before her in the form of a dragon.