Ron stood there gawking, and as well feeling aroused. He had watched as Runt caused Mark to grow and change, becoming as made a female and then equine, was to his senses a mate. Ron felt his cock drop and begin to bloat with an anticipation of his mating with Mark. The fact that Mark was a friend and previously male, failed to matter to Ron as he had accepted what Runt did to him.
Mark stood there as stunned, if equally aroused by the smells of a stallion.
"Hey you two, Ron, you know that sexy smell is coming from Mark?
You are getting aroused by her scent. Oh nothing is wrong now, as he is a she and a mare, being capable to accept a cock of your size, and milk it, giving her and you a real thrill." Runt said as he smiled, admiring his handiwork.
Mark then whinnied as hearing his voice she/he looked at Runt as if surprised.
"What is wrong, you know his smell is affecting you, as is your spicy cunt now making Ron feel aroused, and he wants to mate with you. Believe me, Ron has a real stallion size erection going, as reacting properly now that he like you are horses, animal, beasts of the fields!
"Don't believe me huh, well step this way and look down, see what he has between his legs, but he is horny and has the stallion hots for mounting your backside, inserting his cock, and thrusting, giving him and you your avid thrills of equine style sex."
Runt brought Mark to stand beside Ron as each then a horse knew strange feelings, having instinctive urges, as each knew what they were wanting.
"Damn it Mark, but your scent is overwhelmingly even to me," Runt said, as he reached a hand and with an index finger did trace a line around the outer lips of the mare vulva.
"Here now, Ron you move up closer, as put your muzzle to her tail, now inhale.
Oops there Mark, you know the proper response, you have figured out what became, as what you are, you being now a female horse, a sassy mare, and in the throngs of estrus.
Ron, don't flinch, as her tail Mark holds high by instinct, giving her stallion his best view of her puckered, black donut anus, and of what you want of is below, those glistening wet winking lips of a mare's vulva. Don't shy way, come closer, get the full view or her marvelous winking vulva. See here as her cunt is pursing out a clear liquid, it is slimy, a natural KY jelly for her stud.
Come now, her scent is almost too much for me an Imp to smell, let be as to whose scent is more provocative, even to an Imp or a mare smelling of you her stallion.
Ron, Ron, your cock is swinging, pounding at your rounded furry tummy, while waiting for the gumption to mount your friend. Oops, that was close, you shot a quick stream of Pre, the same to similar of what her cunt is pumping out, it works to sooth your entering."
Ron had heard enough prodding and he shrieked a whinny before he leaped and mounted Mark over her hairy butt.
"Really into it now there Ron, your neighing and mounting, maybe feeling a sense of possessiveness. Akin to thinking that she, Mark is yours for the taking. Forget any worries, Mark is beyond worrying, he is now a she and seems to be liking the fact.
Ah-huh, as lust begets the start to instincts, and a lack of thinking rationally.
Yes, let your cock slide inside, it passing those lusting black lips of mare sex.
Mark, don't you love that sheer delight, feel it as his massive cock strokes along the muscular walls of your mare vagina. F-e-e-l... as his cock slips deep seeking to meet your cervix, to inseminate, feel the heat of his cock!
Ron, yes go for it, begin now your thrusting, feel the full length of what as a stallion is the real you. She is new as a mare, her cunt tight as is her vagina, love it, delight in your mating!"
Ron leaned his bulk self into as over the back of Mark, he taking a bite at the base of her mane near the withers to help hold his balance as he thrusts.
Mark stood soundly on four legs, she not wavering from the bulk weight of Ron as he leaned over her butt, they joined for a few fast minutes feeling their equine style of ecstasy.