Desi was accelerated through his classes at an early age, and at age 17 he was in his third year of college. He specialized in robotics, and had such a deep understanding of it that he could have entered the field before the end of his year, if he so wished. His project for that year, imposed on himself, was to build a robot with a sophisticated AI. Not only would it be able to recognize friends from enemies, but it’d be able to emulate appropriate emotions and possibly even learn, to an extent.
When a bunch of Hyperion operatives tried to recruit him to work for them, he turned them down. One night, when he was alone in the building and working late, the operatives ambushed him and shot him in the shoulder, to stop him from fighting back. As the lead leveled his gun with Desi’s forehead, the robot sprung into life and mauled the Hyperion workers to death.
In order to avoid prosecution/death, Desi fled the planet and got his shoulder patched up by a doctor who was fleeing from malpractice charges. Desi has mostly recovered, but the threat of having to amputate his arm still lingers.
Now a budding Vault Hunter, he’s come to Pandora to study the practical uses of Eridium in robots. He’s fully aware it can be used as a power source for weapons, so now he wants to know if he can power his trusty robo-dog, Arluin, with it. ...He also just really wants some protection from Hyperion, and hey, Sanctuary seemed like a pretty good bet. It was the one place he knew of that Hyperion hadn't been able to destroy yet.
In other words, yes, he’d play very much like Gaige the Mechromancer. His guns of choice are SMGs that cause elemental effects, namely Shock and Slag. ))