It was a warm day in June, and she could feel the nearing approach of Summer as she sat naked on her front porch looking over her large farm. The road was barely visible in the distance, and she had no concerns of anyone seeing her relaxing in the warm sun in nothing at all.
She relaxed onto a softly padded deck chair and rested her legs up on the deck railing. She fondled and gently rubbed her left breast softly and closed her eyes, enjoying the sensation and the gentle breeze flowing over her and between her legs. She imagined a lover, young and with a flatter chest than her own, but with a strong will that was able to command her.
Her hand naturally went between her legs, and she felt over the outer lips of her cunt. She slid her fingers between them and ran her finger up and down her lips, feeling the wetness that was beginning to accumulate. The fingers slipped up, and she brushed her clit, making her shudder a little at the intensity of the sensation.
She worked on her cunt a little more, getting herself worked up enough that she did what she did whenever she got horny and needy. She walked to the barn and opened Saul's stall. He was a smaller pony that had taken a liking to her, and much to her joy he always seemed horny himself.
After opening the stall she guided him into the center of the barn and reached under his warm belly, feeling to his sheath. Sure enough, he was already swelling some for her. She ran her fingers along his length and he let out a small sigh of pleasure. She smiled and then laid herself over a small padded table she'd sat up to make the mounting process easier, spreading her legs for him.
"Come on, Saul, you know what to do."
He did. He stepped over her, and his front hooves banged against the padded table. His back hooves braced against the floor. His cock, swollen now, came sliding out from his sheath and was poking at her backside. It only took him a couple tries for his tip to find her damp slit.
He thrust forward, and she shuddered and gasped. He was about a foot shorter than the other ponies she bred with, so his cock was much shorter as well. It still filled her up, though, and he had no trouble going deep. Her womb had never known human seed, and today would be no different. She was glad to have someone like Saul, as he could reach her cervix and rub it just right without having to thrust too hard.
He pulled back and then drove in again, making her cry out in delight. He settled into a rhythm, and she enjoyed every bit of it. With no one around she was free to make as much noise as she liked, and so she did.
He wasn't a long fuck, though, and after just a couple minutes he was whinnying and huffing. The equine flare on his long cock expanded and stayed stuck inside her body, letting her know she was about to be flooded with warm cum.
Sure enough, the first pulse was a thick one. Her stomach was pushed out a little by the sheer volume, and then the second spurt was just as thick. Saul continued to come, his cock twitching and his hips shifting as his cock flexed.
Sarah loved it, loved being his mare to breed, and she came hard with the pony. Her cunt spasmed and milked him, squeezing him and begging for his cum. When he was finished he stood still and rested on her, panting hard, and she was panting as well.
Then, to her surprise she felt her body starting to shift somewhat, her face growing longer and her body starting to both hurt and feel so good at the same time. Her cunt forming into that of a mare's between her legs, a whinny of her own forming in her throat. She could even feel a tail forming between her ass cheeks.
Saul's cock was still deep inside her, and she could feel it start to swell again, and he began to thrust hard into her, making her squeal out with delight. Her body was covered in a short coating of fur. Her hands stayed hands, but with thick hoove-like fingernails at the tip of each finger. She was becoming half-horse!
She felt her orgasm start to peak, and she came again. Her pussy gripped his cock hard, and she was sure it would make him spill his seed inside her again. She needed him to, so badly, the need to be fucked was screaming in her brain like something she'd never felt before.
To her pleasure, he did. His cock unloaded another round of his thick cum inside her. She could feel her belly getting fuller, and she was enjoying the sensation, and the sensation of being his broodmare, and his mare. After this second load he pulled free, and she could finally examine her body's changes more fully.
Her face was still human, but with a horselike muzzle and a long nose. Her hair had become a dark black mane and her ears had risen up her head. Her hands and arms had fur up to her elbows, and her feet and legs were completely covered in fur, the hooves on her feet large and brown. Her tits were still perky, and they had changed the least.
She gave an attempt at talking, and found she still could, but it was a nasily and sloppy speech. She'd have to work on that. She moved to get up, and felt a tug at her pussy. Her eyes widened, and she looked back. There, connected to her, was a long, horse-like tail!
It was a bit of a shock, but she had to admit the sensation of the tail rubbing along the backs of her legs was nice. She'd really been changed, and was a mare now, a real mare. She examined between her legs and saw a much larger mare cunt there, and it needed to be fucked so bad. Her new nose was easily picking up the heat scent coming from it.
Thankfully, it was a larger cunt now, and she could probably take every pony and horse in her barn with it. She looked over and saw Adrian, her arabian horse, was also out of his sheath and pacing in his pen eagerly. So she returned Saul to his pen and opened Adrian's next, and he ran out egerly.
His horse meat was swaying from side to side under his belly and dripping runny precum. It was a little dirty, and normally Sarah would have cleaned it fully first between enjoying. With Adrain she'd normally just do oral and give him a nice hand job. But today there wasn't time for cleaning. Her cunt needed him in it right now.
She laid back on the table and spread her legs. "Please, my stud, fill me!"
The words were sloppy, but Adrian understood them, and was very happy to oblige. He was on her in a second, his forelegs gripping the sides of the table and his hind legs bracing on the floor. He found her cunt and wasted no time in pushing himself inside her. Some of Saul's cum squirted out of her and on to the floor to make room for her need breeder.
He wasted no time, either, and immediately went into a furious pace. Sarah's eyes rolled back in her head and she moaned and gasped, her body rocking on the table with each thrust. He was going harder than Saul had, and her pussy loved it. She owned 4 studs and 2 geldings, and was looking forward to feeling all 6 of those cocks inside her today.
One after another they filled her, and she came over and over, her new cunt gushing fluids with each orgasm. By the time they were finished she had lost count of how many times she'd came, and she had a large pool of her cunt juice on the floor under her.
It was a wonderful day, and she was happy with her new changes.