Finally the time arrived that she was to be mated. Unexpectedly the anxiety began to build more and more as you got led into a room at the back of the barn. You could tell something was a bit off by the way the humans were talking to each other and you as you entered. It was a fairly empty room with some hay and a couple buckets and one large horse.
You eyed the horse and it looked back at you, it didn't take long for the scent to reach your nostrils. The musky smell of the stallion causes you to become both nervous and relieved as the stallion gets near you. He lets out a whinny and you comply by moving further into the room as to allow him ample room to mount you and dispense his seed. You don't seem to have much control over your body as it seems to be locked in a constant state of both fear and rapture now as the stallion trots around and positions himself properly. He deeply sniffs at the pheromones you are currently expelling.
You let out a series of low whinnies as you begin to further experience a mixture of emotions as the stallion licks at your supple opening. Even though you have been living as a mare for the past year this is the first real experience as one and you quite like it. However that fond moment is soon replaced by more anxiety over the fact that this is indeed the last line that you have spent so long not crossing, after this you reckon you can no longer call yourself a human inside a mare but a true mare and a horny one at that. In your confusion you whinny to the stallion to help you sort it all out, forgetting entirely the horny male might be a little biased. He noses your opening again and you let out another low whinny as you begin to want him more than you do not.
Once again he nudges you and this time you are unable to stop yourself from enjoying the warm ups completely and you lose any semblance of control over your body as you whinny loudly and push your rear in the males nose forcing him to take in your scent. The male lets out a joyful whinny and licks you one last time and take his position. He mounts you. You cannot believe the rush of pleasure as it overtakes you and destroys every part of you that didn't want this to happen as you let out whinny after whinny of pure rapture as you begin to push back on his massive tool. It parts your feminine lips and strikes true as your eyes begin to water and you begin to cry for some reason. You don't think much of it though as your new lover is quick at thrusting but slow at finishing as the two of you take a long role in the hay at last a climax is reached and the two of you whinny in pure pleasure. You collapse and the stallion does so as well as you both fall asleep as contentment washes over you.
You wake up to find...