Blue is about two high school aged girls, Kayako Kirishima and Masami Endo, who find that their friendship is turning into something more, and they are unsure about their future and feel confused about their current life.

The two end up becoming friends, but as the days go on, they each find themselves falling in love with the other and struggle to make sense of their feelings.

Kirishima decides to go off to Tokyo and pursue a career in art while Endo chooses to stay in her hometown and get a more modest job.

This work doesn't focus on expressionistic art and melodrama to tell its story; rather, in its place are minimalist, realistic imagery and storytelling.

In accordance to this style the layouts are muted and many sequences of panels only show subtle movement to highlight a particular emotion.