I was a teenager. A really really really stupid one. Let's get that out of the way first.
I had enjoyed some psychedelic fungi a few hours before the incident and got into a pissing contest with a friend. He was claiming to have masterful powers over his own pain and proceeded to allow my other friends to punch him while he stood there without wincing. Not wanting to be up-staged and feeling quite invincible myself, I proceeded to extinguish two lit cigarettes on my hand, one after the other without wincing. I did it... and to no one's surprise, I have big, stupid, circular scar on my hand to this day.