After all the foreplays your filly finally presented herself, without a second thought you pass the point of no return when your shaft plunges in Megan's wet folds, after a few thrusts your cock twitch and start to grow in length and thickness to better satisfy your girlfriend, she moans again as the new shaft stop growing and fills her completely now, you now sport a complete equine cock.
“Alan, mhhh… Don’t stop”
Alan places his hands on her buttocks for better leverage and sped up his thrusting, causing Megan to synchronize with him to back her rump to enjoy fully the experience, without noticing that their transformation resumed at a faster pace than before.
“I love you honey… “ He said after another thrust, the sensation of his cock sliding in and out of her slick vagina bringing him closer to an incredible orgasm, his girlfriend not far behind if her moans and grunts that he hears are enough clues.
Neither of them were aware of the faster transformation during their mating, their hands slowly balled into fists and transformed in hard hooves, their faces elongated to transform in a short while in furry muzzles and then their fur extended to their navels and started spreading higher and higher to encompass everything under their necks, including their now completely equine arms and legs, that forced Alan to lean completely on the mare’s back for his new inability to maintain balance with only back hooves.
An external observer would be now hard pressed to point the difference between the two horses near the lake and two born equine, but the changes were not finished yet, and the last programmed changes were the most insidious, because the spell changed the way the two lovers perceived themselves.
Alan and Megan did not recognize themselves as human beings anymore, he was a proud and vigorous stallion, living only for personal pleasure and to transform new mares, while she was a beautiful and feisty filly, utterly loyal to her mate Alan and willing to conceive his future foals.
Memories of their human lives are still fresh for the two horses, but with a constant routine of mating the chances of the memories fading forever from their minds is higher the more pleasure and lust they experience.
They were now in the metaphorical edge of the abyss, their orgasms were getting closer, and with that final act of carnal pleasure their physical and mental changes would become permanent, making them property of the zoo.
With a grunt and a final thrust Alan makes the choice for them both, as his explosion coat her inner walls white and bring the mare over the edge, her twitching vagina finally squeeze his shaft as to milk his seed out of him, the first of many orgasms that they will experience as mates at the service of the stables.
Utterly spent the stallion dislodge himself from the mare, without sounds his still erect penis is withdrew from her vagina, nuzzle affectionately his filly and try to talk, but he only neigh and whinny. The stud is a bit upset that they lost the ability to speak, but his new instincts tell him he will not need fancy words to understand other stallions or mares, scents and body language is now enough.
The newly transformed horses stand still as they wait for their new master to arrive with their halters, for a few minutes they explore and admire their bodies until the sound of an approaching person reach their ears, the ears perks as the stable attendant walks in the clearing and greet them with a smile as soon as she saw you both.
She approach and bring out your halters, you don’t resist as she slip the halter in your mouth and secure it behind your neck, you are instead pleased when she inspect your body and seems satisfied, the attendant put the halter on the filly and leads you to the stables for the night, after a moment she start talking but you can’t understand her words, you suspect that it’s an important speech but for you is as she is talking in gibberish, your memories tell you that you should understand her but you discard them as ludicrous, you are just a normal stallion after all.