Game Development Department (ゲーム開発部) is one of the clubs at Millennium Science School.
In contrast to their school's motto, this Department is focused on making retro-styled games; one can mistake it for a typical gaming club.
This club is the main focus of the Millennium Arc, Clockwork Flower Pavane. During the arc, the club is in danger of being dissolved due to A.) only having three members and B.) not having made any notable accomplishments throughout the school year. They often clash with Yuuka due to the club's issues.
All members appear to be references to prominent Japanese eroge companies
Being a faction tag, this should only be used when all members of the group are present and equally in focus.