Luke has always been the athletic type.  In school, while his grades remained average, he excelled at sports ... especially those that relied upon endurance, skill and speed.  
He enjoyed an Athletics scholarship to University, which he completed with average grades.  

Later, he found work in low budget films performing stunts, and found he had a knack and taste for the life ... especially the vehicular stunts.   Buses, cars, trucks, bikes: he did it all.  
And eventually, as his skills and experience grew, he got better offers.  

He has remained a fitness junkie. Body building has never been a focus, though, other than as one element of keeping himself fit and fast.  

As for fighting: Luke's been in his share of fights. Nightclubs, bars, and even some on-set fight training as an extra has helped.  He has never been interested in weapons, like some.  He carries none ... but has become adequately proficient at picking up any nearby items of use during a fight, and hitting the other bastard with them: whether that be a chair, bottle, crowbar or baseball bat. 

Luke is generally a rather friendly and placid creature, though.  He likes the thrills of his work, and riding/driving in general, as well as the relaxed atmosphere (of a pub, the beach or any quiet zone).  


Just recently, when he started 'seeing things' it nearly drove him crazy.  He reacted to such things in the company of others who couldn't see them, which made others (and himself) seriously start doubting the cohesion of his head.  

His mother, Virginia, and sister, Valerie, rallied to his side ... yet neither could understand his sudden 'certainly' in 'his delusions'.  

But Luke has come to accept that, somehow (and he's not sure how), these things ARE real ... at least time him.   
And so, in a sense, he has 'gone on a spirit quest'.  Like the old Kung Fu legends of television past, Luke has heafted his duffle bag, and wandered off into societies wilderness ... just walking from place to place, trying to figure out who he is, and what this weird shit is that is happening to him.  

{Jules: "Basically I'm just gonna walk the earth." 
Vincent: "Whatcha mean 'walk the earth'?" 
Jules: "You know, like Caine in Kung Fu - walk from place to place, meet people, get in adventures. "}

Val and his mother would have tried to stop him going, of course, so he didn't give them the opportunity.  He left them a letter saying goodbye, and promising to return some day ... then slipped away into the night.  

The next year (or several?) Luke spent 'walking the earth'.   Like the 'Samaritan Hobo', he lives off the kindness of others; and endeavors to help people out along the way.  
But his search is always for answers, and Luke quickly came to realize that the answers he needed must come from non-traditional sources: the Occult.  


And so, Luke has sought out those who understood 'unconventional wisdom', and remembered the 'old ways'.  

~~ In a small rural town south of Seattle, he spent a week with a small coven of Wicca, who said that the was more in nature than man could see; things Gaia had created but chosen not to use. 

~~ In Wisconsin, Luke met a street bum with the ability to create whatever he desired, but no longer had the desire to live, yet did not have the courage to die. When drunk, he mumbled about 'other places' and insinuated that he followed a man named Laurence. 

~~ In Denver, Luke sat with a Rabi Who explained that God created this world, and populated it with beast and men.  He gave men the power to dream, and man dreamt of new things to populate the world with.  And while they do not belong here, those things often find a way into our world. 

~~ In the Florida quays, Luke spent one night 'alone' by a fire, talking with some strange little goblin-like man, who drank more scotch than Luke thought possible, and was intent on hearing all the NFL news of the past season.  

~~ On the Cooked River Reservation, in New Mexico,  he became friends with an  Isleta Pueblo elder, and Tribal Police Officer, named Jacob Long Road.   From Jacob, Luke learned that the tribe believes in the existence of the spirit world ... and that, while most Manitou cannot communicate with this world and it's people, some do so through portents, imagery, and omens.  Jacob was a renowned Officer, who, it was said, could solve a crime simply be hearing enough about it.  

~~ In Long Beach, California, he met a Voodoun priestess who called him a 'little god' and claimed his soul; but to this day, seems unable to compel Luke, nor do anything else with it. 

~~ And in New York, Luke spoke with a stage magician who claimed that reflections of the 'old gods' (Zeus, Odin, etc) walked the earth; yet their power was mightily diminished, as very few people truly believed in them any longer. He claimed that new gods were rising: Credit, Ronald MacDonald, Internet and Oprah among them ... new gods that men now believed in.  He said a war was brewing between them.  



The most unlikely Arcana

Wikipedia:

The Fool or The Jester is one of the 78 cards in a Tarot deck. In occult tarot, it is one of the 22 Major Arcana, sometimes numbered as 0 (the first) or XXII (the last). However, in decks designed for playing traditional Tarot card games, it is typically unnumbered, as it is not one of the 21 trump cards and instead serves a unique purpose by itself.

This card embodies Luke ... and Luke embodies the card concept.
The Fool is, simultaneously, the first, and the last ... and neither, and nothing.
It is both Major Arcana, and not.
In a deck wherein every other card holds a specific place, arcane position, and meaning, The Fool refuses to fit in to any hierarchy, and does at it pleases ... and ‘serves a unique purpose by itself’!

Entertaining the Lady
Luke (gladly) feels like he serves ‘The Lady’. 

Pratchett Wiki:

”The Lady", also known as; "She-who-shall-not-be-named ... The 'Million-to-One' Chance - and all of the other chances as well ... The One who will desert you when you need Her the most - and sometimes She might not...", is none other than the Anthropomorphic personification of Luck, as well as the single most powerful goddess on the Discworld, all for the simple reason that (although She has no worshippers and the only temple ever erected to Her was destroyed purely by chance) everybody hopes and prays that She exists and that She'll smile on them. Her suitors can be distinguished by their distinctive repetitive prayer; "please-oh-please-oh-please-oh-please." She's definitely a lady, but She'll quite happily leave Her escort and go blow on whomsoever's dice She pleases. If you think She won't be there for you, chances are She will (or won't), but say Her name out loud and you'll probably never see Her again, though you might. The Lady is the eternal rival of Fate. She is one of the few characters in the series who can, or have, upset Fate's powers over the board when they play games with the lives of people down on the Discworld. While Fate is implacable, The Lady is capricious: Fate plays to win, the Lady plays not to lose. Often Her playing pieces do not appear very powerful. She has never sacrificed a pawn before, or at least, so she has declared.

Luke never invoked her name, nor calls upon her favour.
But he will often behave in a way that draws her attention: if only by amusing her with his antics.
And by doing so, by entertaining her and making her smile, she (by default) smiles upon him.

And he like it this way.
In his own way, The Fool enjoys amusing The Lady’, and earning her favour ... even if said favour only comes because she wants him to survive a little longer, to amuse and entertain her a little longer.