>>280320120
I always imagined Zero and E-soul being one of the first superheros, they were not creating the trust system, but rather willingly being guinea pigs in order to understand it. And as the first generation, they came to know eachother by being a hero duo prior or something. That is, until the Fall of Dawn Incident.
I can't imagine him being an alien, it just seems that a (maybe alien) cult messed him up and used him as the first vessel for Fear.