No. 6 manga omnibus volume 1 collects volumes 1-3 in a larger sized omnibus format and features story by Atsuko Asano and art by Hinoki Kino.
An elite student named Shion lives a seemingly perfect life in the city of No. 6, where life is carefully controlled down to the last detail. However, everything changes one fateful night when Shion offers an injured young man shelter from a storm. Known only as Rat, this boy is a VC–a fugitive living outside the computerized tapestry of city control–and helping him throws Shion’s life into chaos and starts him down a path to discovering the appalling secrets behind the superficial perfection of No. 6.