This work doesn't focus on expressionistic art and melodrama to tell its story rather, in its place are minimalist, realistic imagery and storytelling. The manga ends with Kirishima riding off in a train to Tokyo as Endo looks longingly towards the train.

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. Kirishima knows she is lying and becomes upset with Endo, but ultimately forgives her the two reconcile, and they decide their futures together. When Endo does return, she lies about her experiences and says that she was traveling with old friends. When summer vacation starts, however, Endo goes on a vacation with the man who got her pregnant, a past lover, leaving Kirishima lonely and isolated. Eventually, they begin to date, and navigate the ups and downs of high school together. 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. One day in class, she meets social outcast Masami Endo, who is disliked by other students because she had an abortion. Kayako Kirishima, who lives in Niigata, is almost ready to go off to college but is lonely and unsure of her future. 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 English version, published by Fanfare/Ponent Mon, was released on March 15, 2006. Blue ( ブルー) is a manga by Kiriko Nananan that was serialized in the alternative manga magazine COMIC Are! the tankōbon was released on April 24, 1997.

Blue kiriko nananan manga