According to an audio recording you can find in the first city you encounter, you're a character that was exposed to an extreme amount of evil energy that was released during an event called 'The Fracture'. You come from a land much closer to the Fracture, the desert, meaning your character is more corrupted and unpredictable. This makes you a fascinating subject for the Aether Disc project.

The Aether Disc project takes corrupted civilians and soldiers alike in an attempt to rescue them from its mind altering powers. However, the more corrupted someone is, the more difficult it is for a person to be controlled. This is what made you a challenge to rescue. However, the results that were predicted came true; You, upon being rescued, are more physically capable than any other soldier around. Zenitheans believe that the more corruption someone attains, the more powerful they become.

This massive project brings you back to consciousness stronger than ever thanks to your very own Aether Disc, and Recruiter Mika brings you up to detail on what is next for you.

(Characters based on first availability of meeting or hearing via audio log or word of mouth)

• RECRUITER MIKA YAKIRI
  - The woman who brings you into the project and the protector's guild. Her only personality trait is that she has the ability to appear anywhere she thinks is important. Works for the Zenithean government. According to player Flame Soulis, there's an audio log that implies Mika is not very enthusiastic about her job, or even reluctant to partake at times. Will find audio log ASAP.
  
  
• AMANI
  - Current planned heir to the Emerald Desert you came from (assuming an apocalypse did not happen). She is amazed by the sight of Zenith City's tall buildings and bustling streets, despite The Fracture's damage on the world. Now, as the last of her family, rules over the desert kingdom, which only about 10% had survived The Fracture. Also pretty useless. She makes you fight enemies because she wants to look at things for a while.
  
  
• CHEF BRIMM
  - Will teach you how to cook for free as you level. May ask you to do creepy things for ingredients.
  
  
• SHIN
  - Globetrotting mercenary with the powerful ability to be in (currently) 10 places at once. This bounty hunter will hire you to murder and collect various people and creatures for large XP and cash drops.
  
  
• NAVARRE
  - Originally not trusted by the Zenith City protectors, she runs what remains of the Khiren Tribe. Currently at war with traitors and neighboring tribes of the Amarite Forest.
  
  
• LYRA
  - The main antagonist and the person who caused The Fracture. Believes they will perform better than all previous Kings and Queens

This is all what I have interpreted from all of the resources I've come across, along with what I have encountered in-game. If there is anything you wish to correct, please comment!