There is a reason why human beings are the most advanced among all beasts. It's not the development of technology or self-awareness, as many scientists say. The main reason has to do with evolution: the ability to adapt. This is the survival mechanism that has kept us safe since the remote origins of civilization. Of course, biological factors come into play. When we are in danger or in a stressful situation, our brain releases the adrenaline hormone, which immediately puts us on alert. But there is something beyond that, something more intangible. Every man sees himself at least once in his life at the crossroads of having to fight for what is his or let it be taken away. There is no biology involved there, only balls. Those decisions, no matter how insignificant they may seem, define us. The man who lets another take the prey he had first spotted. The one who always settles for second best, the less attractive female of the tribe. Once you take sides to be the one who submits or the one submitted to, it's hard to cross the line back. Your body adapts and accepts its nature.

Years of civilization had erased that animal veneer that covers us human beings since we lived in caves. Nevertheless, the body is wise and remembers its origins. Now, even simpler acts defined us. The stage was no longer the jungle, but the schoolyard. We no longer fought for food or the most fertile female, but for toys or a place in line to eat. Being strong had taken a backseat; now what mattered were guts and intelligence. One without the other is useless; combined, however, they are deadly. A boy clever enough to know he is superior and with enough courage to take what is his would dominate the world. Moral scruples limit us. Now more than ever, the law of the jungle prevails.

I would like to say that this was what I was reflecting on after getting revenge on Ernesto. That the sight of Amancio lying at my feet was the culmination of all those years of evolution. The guarantee that humans are divided between wolves and sheep. But no, I wasn't thinking about those things. In fact, I wasn't thinking about anything at all.

My heart was pounding as if there were no tomorrow. My nostrils dilated, seeking and recognizing the scents of the room. The sweat Ernesto had left behind, a reminder of the humiliation. The urine with which I had marked him. It's curious how the smell of someone else's urine is unpleasant to us, but our own is satisfying. Lastly, the scent of my drooling cock that had been hard for over an hour. That was the reason why I couldn't think of anything. I felt like all the blood in my body was in my dick, urging me to touch it. I usually joke that my cock has a mind of its own. That's a half-truth. Both of us have an agreement. It signals the urgency of my arousal; I signal how to carry it out. However, I never remember it taking over my body in that way.

Standing as I was, with Amancio kneeling before me, I masturbated wi...