Professor Xenu, or Xezu, was once an ordinary person long, long ago, from a simple world called earth. He lived a normal life until he died, and to his surprise, he awoke in a seperate world fully alive and fine. Tasked to save that world, he did just that at the cost of his life, going on a long adventure. After death, he woke up in another world. The pattern continued. Hundreds of worlds, hundreds of lives, Xezu had been it all. Now he simply studies and teaches others about their worlds.