Lucas is from another universe, where his planet was torn and ruined by a war that seemed to have no end and no start. Where people don't remember the concept of peace and where corpses, ruined buildings and barren wastelands are a common sight.
Lucas volunteered to join the military, even when the place he lived, a sector with less damage, rubble and corpses a decent ways away, weren't obligated to join. It was one of the few, rare places where people could simply live and weren't forced to join the military, and where the military actually tried to keep the bombs, and essentially the ravage of war, away from them if proven convenient. It was practically a safe heaven.
When Lucas joined the military, he was put into a special program where he signed the rights for his life away and was subjugated to experimentation where his blood was filled with serums and poison in an attempt to make the military renewable soldiers, and, perhaps, more useful ones. Resilient. Obedient. And everything else a military could want.
It was a place where no one so much as batted an eye when they heard ear piercing screams echo down the hallway.
Lucas died there. In a matter of speaking. He died out in battle to both test what the program had done to him and to help out in a war everyone - as far as everyone knew - had grown up with only to wake up, three days later, strapped to a metal slab in a room that smelled vaguely like burnt meat to Lucas' tired and frayed senses.
It was there Lucas learned just what it meant when he signed his life away.
And it was there, strapped to a metal slab that still burnt his skin with electric residue still bouncing across the metal, that Lucas learned that his life would never be in his own hands again. Something that was nearly just as terrifying as coming home from playing outside, toy in hand and a smile that nearly split his face as he raced up the steps, only to find the door already open and his parents dead on the floor.
His war torn planet, along with its just as worse off universe, was destroyed when someone decided that if no one else was going to put them down, then they might as well get rid of everything.
Lucas wasn't sure how he did it, but somehow he'd managed to steal a ship, and through luck he didn't know if he wanted, managed to escape to another universe entirely.
Now Lucas has to learn how to survive in a universe that's never experienced the war he grew up in and that's entirely unfamiliar to him. Where he's completely and utterly alone. Side stepping his many, Many problems with the practiced ease of a man who's grown up in a war and would rather suck off a gun than look himself in the mirror for too long, he meets a pair of brothers that will change his life in a way he'd never have consented to if he knew what it'd bring, for the sake of ignoring his problems for as long as it took for something to kill him.
(Not that he'd ever be able to let himself leave them behind if he had the foresight he has now.
The ship Lucas stole was a time machine the military was working on whose entrance is a simple wooden door with something similar to a pocket-dimension housing the huge complex and its many, many rooms. The door was Lucas' choice after he made the place his home, thinking the original thing stood out too much and was something he simply didn't like. He can summon the door with his watch practically anywhere. He made the watch for convenience's sake, It can do a few other things too but its main use is to summon the door. Lucas is also brilliant at making and using weapons. Something he learnt in the military but only really picked up on and leaned into once he escaped. One of the only things that can get him in a somewhat decent mood is tinkering with things, or fixing parts of the time machine or improving it with things that'd help him on the odd jobs he takes to make a living and gain information.)