Set after the events of EX A, it focuses on Cosmic Compiler's continuous search in the "General Answer" (or "GA") which contains a massive repository of data about the alternate history of Humanity. Leos travels to the Earths' of the alternate timelines in an effort to collect more data that might give them a hint for the evolution of mankind. However, standing on their way is a new enemy named Sthesia Awar Acht, whose motives were unknown.