(This is purely made up. Nothing more) I was back home on our farm, my dog, Nike (pronounced like mike but with an n) walked next to me, he was a large dog, for his breed, he had to have been the largest border collie alive. As we walked to the stables to feed the horses while my family was on a trip, I couldn't help but notice how my dog would even take one whiff of my hand and his large 10 inch red cock was out of his sheathe. I also couldn't help but notice I had gone a month without any sexual contact because I had been so busy at the farm. Once I got back to the house an back to my room I tried my hardest to ignore my wetness, but Nike stuck his snout right up against my pussy, my panties where soaked as he licked my wet cunt. "No. Bad boy!" I tried to snap. But Nike wasn't having any of it. He jumped up and started licking my face. His hard slick red cock pressed against my wet panties. Pre cum dripping onto the chair as his hips thrusted slightly. "Oh Fuck it! Down boy! Hold on." I moaned out. I pulled my panties off and laid on my bed, my stomach upright as I patted my shaved pussy. I knew what I was doing was wrong, but right now I didn't care, I was craving cock like a slut, and my pussy was soaked. Nike took no hesitation as he mounted me, humping me aimlessly as his cock didn't reach his target. I wrapped my legs around him, as he jabbed my throbbing clit, his cock finally slipped inside of me, and he pounded into me panting and whining as he did. I moaned out, as his thrusts got wilder. In one thrust he started pounding into my g-spot, and i could feel a fast approaching orgasm, I felt something start popping in and out. I knew instantly it was his knot. And right now I could care less about my orgasm, I wanted him off of me and out of me before he got that knot in me. I looked in the mirror as it just kept swelling, growing to be the size of a tennis ball. I arched my back moaning as I came, not realizing that by doing so I lubricated his cock enough he could push the knot inside of my tight waiting pussy. He then shot load after load of the creamiest, thickest, and hottest cum in my willing womb. I screamed as I came again. I panted as Nike licked up my chest cleaning the seat off me. He started to whine as he kept cumming inside my womb, none of our mixed cum escaping because of his knot being so thick. Once it started to deflate I moved trying to pull back, and he started thrusting again, filling me with more cum as his thrusts where hard his knot inflating again, as his tip pounded the entrance of my womb, rough and hard, that's when lust took over, I quickly caught on the more I moved the more he would stay locked inside my pussy, and keep filling me with cum. I grinded up as he kept thrusting, my movements keeping him in me as I came again, more of his cum filling my womb as he tried desperately to impregnate me with his doggy sperm. I moved more and more, and he kept moving, filling me with his cum, as I came again and again, and again. I relaxed, panting, as his red cock deflated, he pulled out of me after a bit, his cocking making a wet popping sound, as his thick cum started dripping out. Even if I wanted it to stay inside me, because I liked the full feeling, my stomach was even bulging slightly.