I know that the FAQ says that it will become clear through the story as we play but I have played the game and don't quite know exactly what the "original sin" is in relation to the story and the universe.

I need this to explain to my wife why I want to play D:OS II. She said she does not like that I want to play a game that has Original Sin in its title. I tried to explain that it has to do with the games universe and the Source but couldn't really put it all together to help her understand it.

Could someone please let me know why they use Original Sin in the title, Please?