Marceloi

The official back story kicks off with Callista finding the 8 year old boy called Marceloi some 152 years before SW-Fans period, training the boy to be a great Sith Lord... who then some 120 years later decided that killing women and children sucked so thence decided to become one of the good guys after a chance meeting with a warrior princess named Eileen Cross and a bunch of warfare against the Callista bred bad guys known as the Vog'on

Basically, the guy and girl kick a lot of ass across the galaxy, decide each other are hot and have a bunch of monkey sex for about 12 years when Callista catches up with them and blows up a bridge they are on, casting Eileen into an abyss and Marceloi barely surviving and racked with guilt hanging off a girder.

Also racked with guilt over the innocent world the monsters of Callista destroyed, he made his way to the Jedi, rising quickly through the ranks coming out a Jedi Master.