In the futuristic era of the Orbital Calendar 311, humanity thrives in space colony clusters. Akiha Shishidou, a girl from one of these colonies, crosses paths with Leopard, a sinister AI entity embedded within a colony's system. With the support of Itsuki Kannagi, an officer from the Inter-Colony Police, the reserved Honoka Kawai, and the robotic companion Imoko 'Imo-chan' Shishidou, Akiha embarks on a journey of intrigue and danger.