Child of a poor family who grew up in Underbridge. Chances were high that he would become a criminal. But he was lucky:
There was an old martial arts master, that opened a place in Underbridge, where he was teaching kids how to do martial arts and how to meditate. His idea was simple: he would take children form the streets and teach them. He would make sure they stay out of trouble, and grow up to be fine people. And once they had grown up, they would open schools of their own, where they would take in a new generation of struggling youths.
Elvis jokingly calls it a pyramid scheme that will soon collapse. 
Make no mistake: he enjoyed and profited greatly from the structure and order that the training gave him. Nevertheless, he never liked the social aspect of it, and left as soon as he had finished his basic training.
He doesn't want to waste his talent by helping random kids from the street. He wants to perfect his mind and body. He wants to seek wisdom and enlightenment. He doesn't want to settle for less. He doesn't want to be held back by other people.
So now he practices and meditates, he roams the streets of Underbridge, most of the time alone, always looking for ways to further his knowledge.
He admires the consortium for its precision and efficiency. He also thinks whatever secrets the consortium keeps could help himself attain wisdom and enlightenment.
Elvis lives a frugal life - so he doesn't need much money. Still, sometimes he has to take on jobs to pay for food and shelter. Jobs he has done: unskilled worker, hired muscle, bouncer, bodyguard, spy.
It doesn't matter to him whether or not these jobs are legal according to the laws of the city. 
However, he does have a moral code that he follows very strictly.
a) Promises are to be kept, no matter what. 
He keeps his promises, and he expects the same from his business partners.
b) He takes what is given to him, but he never asks for payment. 
(Of course, once a potential client has offered a payment, Elvis will remind them to keep their part of the deal. However, he has walked away from potential jobs, simply because the potential client never brought up the topic of payment. Sometimes he simply helps people in need, under the assumption that they will be generous in return.)
c) He doesn't participate in any form of extortion. Because of this, he performs a background check on all his potential clients before accepting a job. Maybe it was through one of these background checks that he first heard about the Solrath Consortium.
Elvis follows Irori - though more as a role model than as a god.