Couple of my kinks now can easily be traced back to when I was like 12. I would often piss into a glass and try and drink it, and I loved being naked, especially outdoors. I'd take my pyjamas off so I slept naked and put them back on in the mornings so my parents didn't catch me, and I'd sneak out into the back garden, get naked, and lie down in the grass and wank myself off.
I'd also sneak out the front door and go walking round town at night, normally shirtless, hoping to find someone who would take my virginity. Also when I went cycling I'd sometimes go off a footpath or something, strip and have a wank.
I distinctly remember doing this on the hottest day of the year when I was 15, going just off a footpath not too far from mine and finding tree that gave a good amount of shade. I completely stripped down and spent like half the day rolling round in the dry dirt wanking myself off. Then I got home to discover my hamster had died, and I was still agnostic/ sort of believed in god, and felt really guilty as I thought it was my fault cause of what I'd been doing! Wasn't much later I stopped thinking like that though lol.