When i was growing up still living with mum and dad, i had a pet dog (a husky). I had hin since i was 9 and we were best friends. He use to sleep in my room on my bed with me. When i got older and went through puberty and my pussy got wet when i was horny i noticed he would whimper and then get excited. After searching on google why he was doing this i learned that he was actually horny because he could smell my pussy when it was wet. This grossed me out but turned me on at the same time. That night i got naked and fingered myself in my bed. Sure enough he came over to me and started licking my wet pussy. This was the first time i had ever done anything sexual. After 5 minutes and a dozen orgasms i noticed his cock was hanging out and it was red and BIG. My curiosity got the better of me and i turned away from him and got on all 4's (litterally ready to do doggy style). As soon as i was in this position he jumped up on my back and mounted me. I felt him jab and thrust but he couldnt find the hole so i reached back and guided it to the target.... OMG the pain i felt as he thrust his whole length inside me in one go and pumped away furiously was intense. I felt a wetness run down my leg from my pussy and it was a trail of blood running down my leg. My dog and my best friend had just taken my virginity and in a very painful way.... Eventually though just as the pain was turning to pleasure i felt another even more painful jolt run through me as something popped im my pussy.... It was his knot and it was massive. It filled my pussy up to the limit and i could have aworn he had torn my insides. At that point i had never heard of a dogs knot and so was unsure why i couldnt get him out of me. I tried to stand but couldnt because i was locked to him as i felt him cum inside me. Eventually the knot shrunk and cane out of my pussy with an auditable 'pop' and the cum that was trapped inside slowly began to leak out of me. I fell asleep exhausted. When i woke my pussy was still gaping but the cum had finished leaking so i got up to go have a shower. When i returned mum was changing my sheets and i had a hard time explaining why there was cum and blood on my white sheets. After that day i had sex with my dog on a number of occasions until one day my dad walked in in me and saw me knotted to my dog he went and got his gun and dispite my pleading and crying he shot my dog right there and then even though he was still knotted inside me. I will never forgive myself.