As the swollen tip of his equine cock presses against your pussy, you feel a strange tingling sensation spreading outwards from the point of contact. It feels like your flesh is stretching and changing, becoming thicker and tougher as it adjusts to accommodate his massive size. You gasp as your realize your transformation is starting to take hold, your entrance stretching wider and taller.
The tingling intensifies as the pink flesh of your vagina darkens to a chocolate brown, your sex swelling dramatically as it reshapes itself into a mare's cunt. You feel the thickened folds of your new equine orifice part to make way for Liam's monstrous cock, as he starts to push inside you. Your mind reels with confusion and fear, but your body betrays you, responding with a surge of arousal that you can't fight.
With each inch that sinks into you, your body yields more and more, stretching and reforming around his equine girth. You can feel the walls of your new vagina thickening, the muscles adapting to their new purpose. You press and wiggle your hips back, desperately trying to take more of him, your body craving the fullness of his animalistic intrusion.
When he finally bottoms out, his cockhead nudging against your cervix, you let out a whinny of pleasure that surprises even you. Your ass cheeks are now squished against his heavy, engorged balls. You feel so incredibly filled, so utterly claimed by his monstrous horse cock. Your mind reals with the sensation of his length deep inside you, your new vagina clamped tightly onto his bestial shaft.
As he starts to withdraw for another thrust you see stars, the tingling sensation of your transformation spreading to more parts of your body.