Dante had Virgil to lead him through the wilds of the otherworlds, explaining as he went how everything worked. I had Aris.
I don't know that I could honestly talk about the origins of my practice without eventually talking about Aris, but he's not a god or a type of spirit that I can put a finger on, so it's weird and awkward to explain him and I've often put it off.
Aris first appeared when I was, oh, probably ten. At this point I'd been working with Professor Dark and Jareth and what I understood to be fae in the nearby woods, as well as made my first attempts at praying to the Greek gods while studying mythology at school. I didn't know what any of that was, not really, just that my life was full things I shouldn't tell my parents about.
The first thing Aris said to me when I found him in the woods after school was "You can see me?" He was older than me, probably fifteen or sixteen, and instantly replaced my cousin Becky of the leather jacket as the coolest person I had ever met.
I brought him home, not really thinking about what he said until my parents steadfastly ignored him and I realized this wasn't just someone who was in the woods. This was Fairy Tale Rules, which is what I called magical things at the time, but I'd never really had Fairy Tale Rules follow me into the house before. Aris tried to explain why I could see him and other people couldn't, but he wasn't a scientist and I'd not even had middle school physics yet. I built up a vocabulary from myths and fairy tales and pop culture - one of the terms I used to describe him over the next few years was "cap bearer," not because he wore a cap but because he could access the doors between worlds.
We figured out quite by accident that I could travel with him between worlds if I stepped out of my head. I'd learned the basics from Professor Dark without realizing what I was doing, but Aris gave me focus. He was like a big brother letting me tag along once I got the hang of it. After a few months I figured out the knack of it myself.
So, yes, my first "astral spirit guide" was a teenage boy. Maybe that explains a lot, I don't know.
He took me to the realms and places he knew, and as I got the hang of it I managed to drag us other places as well. I ended up in stupid amounts of danger more times than I can count, but like a big brother he made sure I got out most of the time. He introduced me, with the best of intentions, to the young demigoddess who ended up possessing me for a couple of years, but that's another story entirely, and my own fault.
Aris died when I was in college, but I still see him sometimes, through the vagaries of the otherworlds. I owe him a lot, though - he was my introduction to all of it, all the places I could go when I took my body off, and my big brother and my tour guide.