Spoiler warning!
This article contains plot details.

Project Ouroboros was a project initiated by a team of human scientists in the 26th century of our era, when world leaders became aware that the Earth's resources were quickly depleting and that there would be nothing left for anyone. Understanding that, even by escaping the planet, destruction was unavoidable, because the second law of thermodynamics predicted the end of everything, they desperately sought eternity.

Finally, they found a way to reduce themselves and the rest of the world to just chunks of data stored on a computer, at the cost of their memories, qualia, and emotions. World leaders then followed their path and started banning meme (i.e. culture and society, based on emotions and memories) from the whole planet, in order to save themselves and their race. The conflict against meme finally ended, and the whole of humanity was condensed on the Ouroboros Ark.

However, one of the scientists in the team, Joah, was fundamentally against this solution. He felt like humanity could not live without meme. In order to choose, he transcended human nature, and restored information and qualia in the form of the crimson angel, L'erisia, who broke open the database and caused the spaceship to fall and reset the Earth - creating Aria Te'Laria where the Epic takes place.