Terminology
Greecia (ギリシア, Girishia?) is the Befort Children's home planet. Much of Greecia is made up of water, and most things on that planet are also powered by it.
Enma is the Japanese name for Yama, the ruler of the underworld in Hinduism. It is not made clear if Enma is a single entity or not, however it can appear as a large number of dark cylindrical forms. Agi describes Enma as the God of the Universe that seeks to maintain balance, and restore it when it is lost. The main role, as presented by the series, of the Enma while maintaining the universe balance is to keep each soul where it belongs, preventing them from either going to different zones or remaining alive when it shouldn't. Since the Befort Children are in violation with the universe balance, Enma constantly attacks the Befort Children. Enma uses illusions to coax the children into returning to their original everyday lives.
Orsel is the life force in all living things. Grecian scientists, and eventually the GED organization, utilize Orsel to bring people back from the Zone, the land of the dead. Because they have to use such high levels of Orsel to bring someone back, a person can become very unstable. If the person can not control its emotions, Orsel can turn into a of weapon. Orsel is measured in Stilbs.
The Autozone is the machine Grecian scientists use to bring someone back from the Zone. It can also send someone through the Zone and bring them back out of it. The GED, through Gherta Hawksbee, gets a hold of this technology to create their own Autozone, but it ends up having dangerous side-effects.
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