The World of Zero (零の世界) is a part of KeA that allows her to freely re-construct the world.
After Lloyd Bannings's attempt to save KeA, he ends up in the World of Zero. After wandering about, he runs into his deceased brother, Guy. In this world, however, Guy is alive. He explains to Lloyd what the purpose of the World of Zero is. His answer to Lloyd's question why he is in this world, Guy tells him that KeA is considering resurrecting him for the sake of Lloyd and Guy's fiancée, Cecile Neues.
Although nothing would make Lloyd more happy than getting back his brother, Lloyd concludes that that would deny the efforts of those who struggled with his loss and that it is for the best that he would not get resurrected. Guy agrees and is relieved to see that Lloyd has grown so much. Warning Lloyd that there will be "obstacles" to overcome as long as he lives, he waves his brother farewell and he disappears into the light.