Little is known about the history of the organization NUE. Around twenty-five years before the start of the story, research and development began to revolve around cloning angels.
- Nue in Japanese refers to a legendary chimera that has the head of a monkey, the body of a racoon dog, the legs of a tiger, and the tail of a snake. According to tradition, it can metamorphose into a black cloud and fly, frequently haunting people in their dreams.
- In French, the word "nue" means naked.
- The symbol that represents the organization is a cross between the Greek letter psi and the letter for Mercury.