Members: Rio, Yuuka, Noa, Koyuki President Rio Tsukatsuki has maintained a self-righteous and dictatorial management style, not hesitating to hide information or exploit officers and C&C for the sake of the big picture. Meanwhile, member Koyuki Kurosaki neglects her duties to play around, making it hard to call them a cohesive organization. Furthermore, the structure where a single leader monopolized information and authority backfired, leaving them constantly behind in responding to the virus.

Members: Yuzu, Momoi, Midori, Aris As the name suggests, they are a club that develops games, but they also function as a retro game hobbyist group. In Millennium, where the pursuit of cutting-edge science is paramount, they are treated as eccentrics. However, they seem to develop other games as well, including arcade-style cabinets found in game centers.

Members: Neru, Asuna, Karin, Akane, Toki A group of highly skilled agents with top-tier combat capabilities in Millennium. Since the virus outbreak, they have been unable to operate effectively due to a shortage of ammunition. Recently, they have been coping by utilizing various melee weapons.

Members: Utaha, Hibiki, Kotori Home to many geniuses in machine manufacturing and repair known as "Meisters," they are exceptionally skilled, particularly in hardware. Their inventions are highly valued throughout Kivotos. Using their skills, they handled the production, repair, and modification of weapons within Millennium, but after the virus spread, many facilities were destroyed, leaving them barely able to maintain and inspect the remaining equipment.

Members: Himari, Eimi, Kei Their purpose is to investigate and research "scientifically inexplicable phenomena" occurring throughout Kivotos, such as the occult and OOPArts. In the process, they often touch upon matters that delve into the very nature of Kivotos itself. Immediately after the virus outbreak, they distributed the best possible countermeasures to those around them.

Members: Mirai, Tsubasa As the name implies, they develop suspicious products based on "pseudoscience" that claims scientific utility without verification. In the past, they have pursued dubious projects such as "Water Remembers," pyramid power, and electromagnetic wave prevention stickers.

Members: Chihiro, Hare, Kotama, Maki They claim to be a white-hat hacker group, but except for Vice President Chihiro, the members have low ethical standards and frequently cause trouble on whims, leading to lectures from Chihiro when caught. After the virus spread, the collapse of infrastructure made it difficult for them to operate properly, and they now focus on securing supplies in small ways.

Members: Sumire, Rei A club dedicated to improving physical strength and ability through various methods such as roadwork and weight training. True to Millennium's nature, they train based on theory. Consequently, after the virus outbreak, they have become invaluable for transporting supplies via manual labor.