Tony woke with the sunrise. He wouldn't have had much more time anyway. There were stable hands and a veterinarian making rounds almost right after that anyway. Tony watched it all while eating oats left in a sort of feed tray at the edge of his stall. The stables were a pleasant hive of activity. A few riders came in very early and took their horses out for training rides or just for fun. Tony knew that Claire didn't get up this early, so he knew he'd have to wait at least a few hours to change back to human form. He wasn't particularly worried. He found life as a horse amenable. Just the feeling, even standing there in the stall, of his power, of his muscle mass was pleasant and fascinating.
At last, the vet and stable hand who'd been making rounds among the horses got to Tony and the horse next to him. Right away, Tony saw that something was wrong. The vet and stable hand cast a bunch of furtive glances around to see if anyone was watching them. But Tony relaxed when the vet, a plump woman in her late 40's dressed in jeans and a sort of tweed jacket approached him from the front of the stall and cooed his name over and over while rubbing his muzzle. Tony was giving himself over to equine pleasures and this felt rather good. She also gave a very pleasant tub to his ears.
"Ohhhhhhh Tony Tony Tony. What a pretty Arabian you are, huh? What a pretty Arabian you are"
She offered him a huge carrot and Tony carefully chewed it down to the nub without coming anywhere near her fingers. He was in the process of doing so when he noticed the stable hand in the stall. He had already attached two metal sleeves, almost like manacles, to Tony's front legs and with two loud clicks, affixed two more to Tony's rear legs. They were joined by a rope and the result was that Tony could not kick with his powerful rear legs without pulling his front legs at the same time. Resistance to whatever they intended was now impossible.
Tony made the loudest sounds he could, over and over. He could see, out of one eye, that the vet looked as if she wished he would quiet, but Tony kept making noise till another stable hand approached. Tony quieted with the approach of the white haired stable hand.
"Jeez, what's the problem here?" he asked. "I've never seen Tony give even a lick of trouble"
"Seems a bit colicky" said the gaunt stable hand behind Tony. Tony wondered what the hell colicky was supposed to mean but he didn't ruminate long. He felt the stable hand behind him cup one gloved hand under his balls.
"He didn't leave anything on the floor yesterday or last night and look at this" said the gaunt one tapping Tony's underside just in front of his legs and then when he got closer to Tony's rear, squeezing Tony's balls hard just as he tapped. Tony grunted in pain.
"Just like Jimmyjack. Remember that one doc" suggested the stable hand at Tony's rear.
"Yup, took a turn for the bad all of a sudden and didn't get better till we gave him a good, strong enema"
Enema! Tony grunted his disapproval but the stable hand only laughed.
"Sounds like he knows what he's in for" he chuckled and went off to distant stalls. Again, the gaunt stable hand and the vet looked around furtively.
"First clean him out but good" the vet ordered. Tony looked back and saw the scrawny stable hand pulling on a latex glove that went all the way up to his shoulder.
Oh no! He felt his tail get pulled aside and then the gaunt gloved arm plunged inside him. Tony grunted with displeasure but not for long as the vet slapped a sort of cloth muzzle onto him and fastened it tight with velcro. Tony couldn't open his mouth now. He could just breath out his huge flaring nostrils and take it. And take it he did. He felt the stable hand reach further and further inside him, the latex fingers scratching and tickling his bowel walls. At last, Tony could feel the man's shoulder pressing against his giant equine anus. He felt the man's hand flexing and feeling around inside him and then he felt the man pulling out, trying to scoop any and all feces within Tony with him as he went.
"Clean as a whistle" he heard the gaunt man say.
"Good, we want to make sure this stuff has the full effect" said the vet and Tony realized he'd been so distracted by the stable hand's progress through the interior of his Arabian horse body that he hadn't even noticed the vet circling around him. He looked over his shoulder at them and saw, to his shock, the vet produce a syringe that could have injected a 12 ounce soda into him. It was filled with a bluish liquid. Rather than simply getting an enema, which would have been bad enough, Tony realized they were going to inject some sort of chemical into his rectum for some reason.
"This'll make sure he's a little off tomorrow?" asked the stable hand as the vet prepared the syringe.
"Yup. We're getting better and better at mixing these little cocktails up. This one'll make Tony here feel a little off his feed and also make him unwilling to do as he's told. And by the morning after that, it'll be out of his system."
With that, the vet attached the syringe to a long plastic extension and jammed it into Tony's ass. Tony smouldered with anger as he felt the cool liquid injected deep inside him in one long spray and then, just as the plastic extension was pulled out of him, he felt what amounted to a rubber equine butt plug shoved into him. Ow! It felt like they had jammed something the diameter of a saucer inside him.
"No sirree. None of that'll be dripping out of Tony" laughed the stable hand and Tony heard them talking as they went away. "Too bad Heather owns that roan. I'd really rather see Tony win but Claire's family doesn't own the place . . "
Tony fumed. If he'd wanted to help Claire win the contest before, he'd positively run through walls for her now. He could feel the fluid inside him, still. He resolved to try to do something and lowered his rear to make the fluid flow to his anus. He could only shuffle backward a few inches at a time, but backed up to try and get his rear against the boards of his stall. After a minute, he got there and managed to get a vertical stud pressed hard against his rear right next to his hole. He wiggled and flexed his rear over and over till, finally, he could feel the edge of the plug catch against the stud and with one deft wiggle of his giant ass, wedged the plug out with a -pop-. Then he sat down, almost on his haunches like a dog and making sure to spread his huge cheeks apart. He spent the next several minutes constantly trying to shit, working his sphincter to get the fluid to drip out of him. It might not matter but if he couldn't transform back to his human self before the contest, he didn't want to be drugged into being an unworthy steed for Claire.
An hour later, the gaunt stable hand showed up. Tony quickly stood up but wondered if he'd notice that Tony had gotten the plug out. But the stable hand wasn't going to notice much. Tony could smell the alcohol on his breath quite clearly. He reached for Tony's anus and the plug and stumbled, falling against Tony's huge butt. He steadied himself and then bent to pick up the plug on the ground, not questioning how it had gotten there. He undid the clasps tying Tony's front and back legs together and stumbled out of the stall.
Off my feed and unwilling, huh? Well, I don't feel like that at all, thought Tony, but just the same, when Clair showed up and fed him half an apple while whispering that they were waiting for him at the east end of the property, Tony was very happy.
Claire saddled Tony up and rode him out to the east end of the site. She let him drink a little water from that same pond but quickly pulled him away and continued on up a slope covered with sparse pines to a dirt access road. There was Jeff and Mark. Claire stopped Tony in the middle of the road and then took the saddle and reins off him. Jeff went through the restore function and Tony felt the electric wave pass through his half ton Arabian horse body. Quickly he lost mass and went through the reverse of the process the day before, tail disappearing, hair giving way to soft skin and all his features resuming their human proportion.
Tony walked to the side of the car opposite Claire for modesty. Mark tried to hand him some clothes, but Tony refused them. He told the others what had been done to him, the phony enema, the chemicals and what the vet and stable hand had said. He asked Jeff to try and figure out what had happened to the chemicals that had been injected into him. While Jeff did that, Claire fumed.
"So that's how Heather keeps winning year after year! If anybody's a threat to beat her they just fuck with her horse! Aaarrrggghhh!"
She went around the side of the car to Tony, expecting that he had something on by now and asking, "Are you sure you're okay? Um, why are you still naked?"
"If there isn't any of that stuff left in my, I want to be changed back into being an Arabian horse right now. I want you to ride me every minute possible before the contest so that I respond perfectly to your commands and you win. I don't want to let those people profit by cheating. I want you to win."
Claire hugged him and they kissed. Tony could feel himself starting to become erect so he turned away from her and faced toward the car. "How 'bout it Jeff?"
Jeff cleared his throat. "Well . . okay, there it is. The chronivac will list the things it deleted from you in the course of changing you back, but you have to go through a bunch of menus to get to it. It says you had some kind of chemical, it gives the chemical symbol here, a bunch of C's and H's, all through the lining of your um rectum and that it just threw it out in the course of making you human Tony again"
"Great!" said Tony. "Zap me again. Turn me right back into a horse. I want to be ridden from now till that contest, so that I don't let Claire down"
Claire hugged Tony and patted his rear. He felt in danger of becoming erect again. He stepped to the front of the car. "Zap me, Jeff!"
Jeff quickly went through the chronivac menus and Tony felt the electric wave pass through him. Again, he gained mass and covered with fine, light gray hair. He felt his penis swell massively and then stick to his lower abdomen. His knees reversed from bending forward to bending backward. A tail sprouted at the top of the crack of his ass and his ears shot up. His hands and feet coalesced into dark hooves. His face grew quickly forward into the muzzle of a horse, nostrils spreading, mouth enlarging and teeth growing several times larger. Finally, he felt his sinew grow and swell, particularly his spectacularly large rear.
The transformation complete, Claire hugged her equine partner and saddled him. She rode Tony all the rest of the day, never leaving the saddle except to use a bathroom. She even ate atop Tony, munching a salad procured for her by a stable hand atop her trusty tabletop of a steed. She ran Tony through the show jumping course over and over till he could have run it blindfolded. And the more she rode him, the more Tony became accustomed to responding to the tiniest signal from her. Did she squeeze me harder with her right knee than her left? That meant to do one thing. The slightest tightenting of the reins meant another. He could feel the merest shift of her weight atop him and knew how to adjust his momentum as a result.
Tony knew that the mythological character of a centaur, a man's trunk, arms and head atop a horse's body was believed to be the first reaction to the appearance of an ancient cavalry man of peoples who'd never seen a man riding a horse. He felt like he and Claire were one being like that now. They certainly weren't malevolent or scary, but when the sun went down, Tony felt like they'd achieved their goal. But he didn't want to interrup the tightness of their master/beast bond and when Clair asked him if he wanted to go back to being human that night, Tony shook his head. Claire hugged him. She led him back to his stall and fed him. As it got dark, Tony lay down amid the hay and onto his left side. Claire lay next to him, her arm over his neck, rubbing him slowly as he grunted and breathed. The gaunt stable hand was closing things up and saw her there. He tried to convince her to get out of there. He said that Tony had been uncooperative just that morning. Claire said that she'd take her chances.
She was surprised at how calmly Tony slept. He just breathed softly in and out for eight hours, his huge chest rising and falling alternately. She wondered if he was sleeping as a human or a horse, mentally. She leaned toward human when she saw his incredible erect penis in the morning. Tony appeared to want to hide it from her when he woke and saw her there, moving to the opposite side of the stall, but Claire playfully slapped his huge phallus and laughed. "When it's human size. You were more than big enough before, but that?!" she burst into more laughter. "But maybe you dreamed of me being a filly, huh?" Tony looked away from her and Claire laughed anew then patted his muzzle. "You're an Arabian horse for the moment, so that's okay"
Claire rode Tony with a confidence that she'd never had even at her best moments with Gingersnap. Neither she, nor her boyfriend mount, felt any anxiety at all. When it was her turn to ride Tony, they negotiated the jumps perfectly, without so much as even an extra stutter step between jumps. It was as precise a performance as any observers could remember. Claire won easily over Heather and had a score of joyous pictures taken atop her mount, her boyfriend the Arabian horse, Tony.
At the end of the day, Tony was in front of Jeff's car at that same dirt access road and Jeff outlined a change to their plans. He would change Tony back to his human form, of course, but everyone would remember Claire's performance atop him as her performance atop her horse Gingersnap. Arabian horse Tony and Claire both nodded to that.
Back in his human body, Tony helped Claire trap the drunk stable hand who'd helped the vet try and drug him. Tony stayed by her side for protection while she told the drunk that they now had him on tape drugging three different horses who had been the mounts of Heather's closest competitors. While other horse owners listened on tape, the stable hand crumbled when presented with more and more evidence. The vet ended up being fired and her license removed. Heather never rode again in that area.