When I was a teenager my parents sent me and my younger sister to spend summers on our Uncle's farm in northern Maine. It was way off the beaten track and very secluded - no power, cable, internet, or phone service. When we were there, we were there for the summer.
Although we didn't have all the electronics we kept busy helping on the farm and with meal preparation. One day I went to the barn to get some hay and found my uncle Robert there watching 2 of his horses mating. The stallion was sniffing the mare, his cock engorged - long as my arm from shoulder to hand.
Once the mare turned the stallion reared and mounted her quickly. His cock burying deep inside her. He pumped once or twice and pulled out, his seed spilling from her and the end of his penis in thick gobs. I must have made some kind of noise, because Robert turned around and saw me standing there. He stood there for a minute quietly watching me when the mare whinnied as the stud mounted her again.
He waived me over to join him at the stall's gate. I could see the mounting from behind, the stud's long, thick cock sliding in and out of the mare. The air was thick with their musk and the smell of the stud's seed. As I stood transfixed I realized my uncle was moving, looking over I saw he had unbuttoned his overalls and was stroking his cock as he watched the pair.
Although I had seen plenty of images on the internet and heard stories from my friends at school I had never seen a man's cock in real life. When I looked back up I saw my uncle was now looking down at me. Watching me as he stroked his cock. He didn't say anything, just kept running his hand up and down the length of his erection. Suddenly, he grunted and a long string of his seed shot out and landed on my shirt. The next several strings landed on the hay covered floor between us until it became just a dribble. Afterwards he tucked his cock back into his overalls and walked off, as if nothing had happened.
Today I am 28 years old and 12-years have passed since that incident on my uncle's farm. While Uncle Robert is long gone and the farm sold I still masturbate almost every day while watching videos of horses fucking. Don't misunderstand, I have no interest to be with a horse (or any other animal), or become a mare to be bred, but when I want a hard, strong orgasm I masturbate to those types of images and everything just explodes. Even when I'm with a man I imagine us having sex in a stall with a mating pair or horses in there with us. The smells and sounds surrounding us, adding to our own.