Echo traveled across the Milky Way (with three others) and came to Earth and met Eris eventually forming as the Archivists after a whole thing getting worried about Crank (Kirk's past self before getting controlled by Noproxites) and ending out getting kicked off their planet.

Echo is extremely smart as he's been Crank's roommate for a few years and been studying his research notes. Echo is nice to most people and scientists. He also wears a glasses because he has bad vision in the only eye he has.

Eris was genetically modified by Crank and is a tiny bit scared from being his henchwoman but she's brave and still can pull herself together after all those times. She's extremely friendly to everyone.

They are actually Otherkinds from the planet of Eden in disguise and here because they are worried about Crank aka Kirk Odd and to learn more about Earth and possibly help out around the Sanctum. They also study the Sanctum with the scientists and eventually move down there with the other 3 Otherkinds.

Using bits of technology stolen from Crank's Lab their planet and their alien powers, Eris and Echo lead the Archivists. They hope to complete their goals.