The mare blinked, nodded her agreement, and they both took a breath as the horse stepped forward, unexpectedly lowered her neck to reach his groin with her face, and glanced up.
“S-Sure.” Jason shrugged. “You do you.”
The mare let out a weird hybridized whinny that Jason realized was an attempt at a laugh and plunged forth. She extended her heavy tongue, slathering it over the opening of Jason’s sheath, and he jumped.
She looked up quizzically, drawing back a little. “B-bhad?”
“No, just... new,” Jason whispered, reaching down to stroke the horse’s neck and offer her reassurance.
The mare nodded, and went in for another lick. Her tongue was firm and textured. It... felt good. Took a little bit of getting used to. Like everything else, she was very strong and didn’t quite know how much pressure to use. Soon enough, Jason felt himself rising, putting both his hands on the mare’s powerful neck and massaging it. She seemed pleased with herself, offering lick after lick to his sheath and his balls, getting much more confident and adventurous. Had his balls grown? They seemed a little heavier.
In any case, Jason stood back and let the mare work him, grinning in delight and offering her encouraging pets as his tip popped out of his sheath and the flaccid length emerged.
“You made me drop,” Jason whispered gently.
The mare smirked playfully at this, a sly and mischievous look in her eyes he was staring to love, and she snorted, the heat of her breath hitting his length and making it tingle.
“I’ll take it from here,” Jason whispered, reaching down and stroking his length. Oh fuck... it was thicker! As it began to grow to erection once more the latest change was obvious. The length was almost a foot now and it was much plumper. The medial ring was more pronounced as he grew hard and the flesh felt heavier and thicker. It was also stiffer, inflating to a firmer and harder erection than Jason had ever experienced before.
The mare watched the display with clear arousal and began to turn again, presenting herself.
“Dooo... meee...” she rasped. “Cowboooy...”
“Yes, ma’am,” Jason blushed.
Again, they coupled. Jason grunted as the mare helped him in, angling her thick ass again and pressing him in.
This round was much rougher, and both seemed to enjoy it. The horse gyrated her ass up and down while Jason hammered. This time... the changes didn’t wait. In mid thrust Jason felt the tingling and grunted, eyes wide in shock.
“G-Grrrrowwwing?” The mare’s eyes widened, gasping in delight. The sensation of feeling the male’s horse cock filling her bigger was intensely erotic.
Jason screamed as he came. He bucked wildly, giving her everything he had, and whimpered as the horse’s delicious ass pushed back on him.
He drew out, spent, gasping, and fell backwards onto the grass. The mare turned, pussy dripping, and her clear panting excitement was obvious.
Both their eyes widened. Fourteen inches. A big long fourteen inch horse cock beyond what a man could ever hope to grow. And Jason was flared. His tip was wide and flanged, the urethra had pulled downward from where it usually sat, the ridged head still pulsating a little. The length was nice and thick. It was starting to look like a real horse dick, and that excited Jason deeper.
Apparently it excited the mare too. She shifted on her hooves and was quite turned on, glancing around nervously.
“W-What’s wrong, girl?” Jason panted, his horse dick starting to sag and lazily shrink as it softened.
“Neeedh... get offf.” The mare gulped. She turned suddenly, spying a nice strong oak tree that was about the right texture for her purposes.
“I could help you with that,” he panted. His cock was now shrunken over and inverting back into its sheath.
The mare shook her head and positioned her back legs in front of the tree, thudding her rump against the bark and letting out a relieved sigh. “Takkkh too longggh.”
“Eh, whatever.” Jason shrugged. “Maybe next time.”
The mare winked and began to rub her pussy up and down on the tree trunk, winking at Jason as he watched her get off. She began to build up a rhythm, gleefully scratching her itch, and without any shame at all the animal began to pant, quickening her pace. Eyes closed. Fantasizing. Her jaw dropped.
Jason watched in amazement, glancing down at his penis as it slurped back into it’s further thickened housing. While the mare continued to get her relief, Jason probed at his sheath, feeling the warm thick flesh, rolling it between his fingers. It was quite pronounced and protective now. He felt oddly safer having his huge new member tucked away like that instead of having that pathetic little human dick hanging down. It felt natural. Right. As he explored, his eyes widened. His balls were much bigger. Fuller. Rounder. More pronounced, and they too were turning dark and thick. He gasped as he lifted his eggs and found his taint dark and blackened as well. He wondered if he had now had a horse’s anus as well.
A sudden flurry of movement caught his attention and he glanced back at the mare. She was trembling, eyes clenched, brow furrowed. Her body was shaking violently, throwing leaves off the rustling tree she was using to masturbate, and Jason turned. He realized she wasn’t cumming. She was changing again. He watched with wonder as she grunted, snorted, and finally let out a clear feminine moan as the tension released from the passing of her transformation.
“Yes!” The mare said in a perfect and husky voice. “YES!”
She began grinding herself against the tree harder and opened her eyes, shocked, her gaze falling to Jason.
“I can tallllk!” She whimpered, near orgasm now. “I can talk!” She threw her head back, dug in her back hooves, and with passionate abandon she ground her pussy into the tree bark, gasping, throwing her head back, kicking her front hoof out.
She came. It was quite a sight. The horse let out a terrific whinny of utter climactic satisfaction, teeth gritted, snout in the air, and slammed her ass into the tree, cracking the trunk with her sheer strength. As she came down, panting wildly, eyes twinkling, she pulled away from the tree and a thick strand of white lady jizz drizzled down and splattered on the grass.
The horse staggered as she caught her breath, chest heaving. “Oh, I’ve never had that happen before!”
“Y-You’ve never...” Jason trailed off.
“Hey, you lock me in a stall and won’t let me fuck the studs!” The mare threw her mane back and chuckled. “Yeah, I’m a little pent up, buddy!”
“Sorry...” Jason said sheepishly, looking down nervously. “Hey... uh... can you... look at my butt?”
“Huh?” The mare’s face wrinkled in confusion. She stared as Jason bent over for inspection and let out a giggle.
“Do I have a horse... hole?”
“Yeah, honey,” the mare nodded, still catching her breath. “Yeah, you’ve got a horse pucker. It’s not done yet, though, if that makes sense.”
Jason stood up, suddenly aware of how his asshole was now rubbing as he walked, and gulped.
“Hmmm!” The mare chuckled darkly. “Oh master Jason, what did you do to us?”
“I... don’t know, honestly... it just... kind of happened.”
The horse nodded, still panting off her intense orgasm. “Not complaining, yeah? I kind of like being sentient and able to talk. I feel so weird, though, like stuff has shifted around inside of me.”
It was then was Jason’s jaw dropped and he gasped. He had glanced down at the horse’s hooves and something caught his eye.
“What?” The mare glanced down.
“Your hooves!” Jason gasped. “Look at them! They’ve changed!”
Both horse and human stared in shock. The mare lifted her foot for study and they both exchanged a nervous look. Instead of a solid mass of hoof clear muscular protrusions sort of like knuckles had emerged above her ankle and her hooves had split into three big chunks. She couldn’t move them yet, but it was clear what was happening.
“The back ones, too...” the mare whispered, nodding towards her rear legs. The back hooves had fractured in the same manner. “Fuck...”
They stared evenly at each other and gravity of their sexual exploits was becoming apparent. “Fuck...” the mare repeated, lifting her hooves and inspecting them one by one in a mix of curiosity and horror. “I’m getting hands and feet, aren’t I?”
“Yeah, and I’m getting a horse dick and ass,” Jason gulped. “It’s... reciprocal. We both get a little further along. But... to what?”
“ A-Am I gonna go on two legs like you? Will I be a horse woman? A human woman? I-I don’t wanna stop,” the mare admitted. “But how the fuck are we going to deal with this?”
“I don’t know,” Jason gulped, suddenly feeling sick again. “How the fuck am I gonna explain a horse cock to my wife?”
“Mistress Taylor?” The horse’s eyes widened in shock. “Oh fuck me, Jason! You’re right! What the fuck?! You cheated on your mate with me!”
“I-I’m s-sorry!” Jason began to pace nervously, the crickets beginning to chirp as night fell around them.
“M-Maybe she’ll like your big horse dick?” The mare offered sheepishly, head falling.
“How are we gonna explain this...” Jason repeated, covering his mouth.
“Okay, look,” the horse glanced around the meadow conspiratorially. “We have to control ourselves. We’ve been fucking all day. Let’s... try to restrain our urges a little. See if we change back a little, or if this is permanent.”
“I think it’s permanent,” Jason gulped, cupping his sheath and bouncing it. “I mean, I hope it is. For you. Like, if it’s temporary you’ll turn back into a normal horse again.”
“Oh, that’s fine!” The mare snorted, rolling her eyes. “You can just fuck me back into existence again!”
Jason turned beat red and gulped. “Y-Yeah...”
“Hey...” the mare approached, suddenly gentle and oddly calm. “For what it’s worth, I’m really glad you did it the first time.”
“W-What?” The human cringed, still blushing.
“No, really, honestly. You’re my favourite human, buddy. You should know it felt really really good for you to bond with me. Sexually.”
“Really?” Jason gaped. “Are you serious? You’re not grossed out or...”
“No, it was nice. I don’t know if I would’ve responded like I can now, but I was okay with it. I felt love. Like, care for me. Even if you were just using me to get your rocks off. Like, uh, my horse brain went oh, the master is mating me. Okay, I’m cool with that.”
“Mmm,” Jason looked away, mortified.
“It happened,” the mare seemed to shrug gently, bumping her nose into Jason’s chest playfully. “We’re gonna have to deal with it now, right? You’re gonna have to deal with your missus. I’m... gonna have to deal with being intelligent now.”
“Yeah.” The human nodded.
“Uh... we should get cleaned up. And, uh, I can smell your pants from here, just so you know.”
“Oh.” Jason blushed again. “Are they far?”
“Nah, we can pick them up back up the hill. Don’t worry about that.” The horse sniffed deeply and looked around, as if trying to figure something out. “Yeah, they’re north up the hill. Your scent is so strong.” She paused, feeling a fluster of arousal again, and Jason caught the now familiar look of the mare smirking.
“No... we can’t. If we keep going who knows what the fuck will happen next.”
“Yeah, yeah, you’re right, we’ll get going,” the horse agreed awkwardly. “Just... don’t be surprised if I’m a little frisky while you’re riding on my back. It’s hot for me.”