No6

No6, also written No. 6, is a designation used in various contexts, but it is best known as the title of a 2003 Japanese dystopian novel by Atsuko Asano. The story is set in a highly regulated, disease-free city called No. 6, where society is stratified and citizens are monitored by state authorities. It follows Shion, a privileged boy, and Nezumi, a fugitive from the outer sectors, as they form an unlikely alliance and uncover the dark truth behind the city’s apparent perfection. The novel explores themes of surveillance, class disparity, and the costs of utopia.

An anime adaptation, also titled No. 6, was produced by Studio Bones and aired in 2011. The series retains the core relationship between Shion and Nezumi and translates the novel’s social critique to a visual medium, expanding on world-building and action while staying faithful to the central premise.

In broader usage, No. 6 is also a generic designation for items or episodes that are numbered six, and may appear in contexts unrelated to the novel or its adaptations. The term can appear in product names, catalogs, or media titles where ordinal numbering or stylized branding uses the numeral “6.”