The narrative is set in a city rumored to consist of thousands of levels. Within a decommissioned zone, thousands of levels overlap one another, making it impossible to distinguish sky from ground or to determine which direction is up or down. Perhaps the original intent of this story is to unravel the mysteries bound to this time and world. For the humans who discovered this vast, rare multi-level city, the enigmatic protagonist "Kirii" wanders in search of the "Net Terminal Genes" that remain uninfected. Kirii's burden and his quest for the "Net Terminal Genes" constitute a unique goal and form the core mystery of this story. Log1 through Log6 contain the story of Cibo, which was not included in the original works. It follows Cibo, who strayed away with Kirii and wanders about. A disc discarded in the rubble. Cibo begins downloading. Whose "Memory" will he ultimately acquire?