I smiled, walking hand-in-hand with my horse jockey of a girlfriend to the races. “You sure you’re okay with this?” I asked with a smile, looking Cass in her golden eyes.

“You sure you’re okay with being a mare?” She smirked, reminding me of the track’s policies. Apparently the owner had read Game of Thrones, and had decided it was too easy to sabotage a stallion.

I nodded eagerly, cupping her hand in mine and giving it a gentle kiss. “Of course.” I smiled, taking a step back to proudly expose my naked body. “Just to give you one last look before you get to be the one on top for once.”

Cass giggled, swatting my arm. “Scandalous. Now… ‘Camptown Races Sing This Song’.” She said with a small blush, uttering the trigger phrase for my ChangeLover’s transformation serum.

All at once, a shudder ran through my body, and I threw my hands to either side of the stable door to steady myself. “Whoa!” I yelped, shuddering again from head to toe as a mane raced down the back of my neck; my hair pulling into my scalp so that only the mane remained.

“‘Whoa’?” Cass smirked. “That’s my thing to say.” She walked up to me and kissed me on my thickening lips, nibbling gently on them as they grew dark and thick. This was always her favorite part of the change, so I eagerly obliged her boy opening my mouth.

As I’d expected, she took the invitation happily, trailing her tongue along my teeth as they grew flat and blocky; moaning as my tongue expanded against hers. My face began to stretch out into a snout and she giggled as it pushed her away.

Then she pet my widening nostrils happily, watching as my face began to sprout a lush black fur. “My beautiful mare.” She whispered, looking me deep into my eyes even as they slid to the sides of my reforming skull.

“Nuhhot a mare yuhhet, buhhaby.” I managed, working hard to speak with a horse’s mouth. Then I felt a sharp pinch that lasted but a second between my legs, and I blushed. “Nuhhever muhhind.”

My voice was warbling more and more, and I realized I wouldn’t be long to keep my speech. “Hgnyy luuhhhvvv yuuheeeee!” I whinnied as my neck began to extend, drawing away from the rest of my body. My mane grew with it, and I tossed it out behind me happily.

Sure, being deprived of my manhood was a loss—but all of the muscles I was starting to pack on was more than a win! I fell to all fours in preparation of what was to happen to me, my body rippling as it grew in bulk, getting so large. I needed this strength if I wanted Cass to win, and I wanted her to won more than I’ve ever wanted anything in my life.

My hands and feet ached beneath me as my arms ached; my legs stretching as well. The added mass to my body was making it almost painful to stand, my skin hurting from the pressure. Thankfully, this pressure eased up an instant later as my skin darkened and turned to a thick enamel.

I scuffed my new big hooves against the ground with a horsey smile, looking up to Cass and nickering softly. This was going perfectly; more than perfectly! The last things which I’d need were already coming in: a long and sleek tail; my soft and controllable ears; and my big horsey torso.

I shivered with pride as my trunk finished its change, and just like that I was a transformed racehorse, ready to be ridden all the way to the finish line. We’d chosen ChangeLovers instead of TransFun for the more vivid instincts, and I could feel a racehorse’s mind pressing against me own, telling me how to win.

But first I needed a saddle. I looked to Cass with another nicker, tossing my mane over the left of my neck with a smile. She read me like a book, turning around to pick up the leather saddle. “Is this what you want? Want to feel my weight on my back; my breath on your neck?” She purred with delight.

I nodded eagerly, my big head bobbing up and down. I wanted it so badly! I had no idea that I could still feel the way I did for her as a mare, but somehow my love for her was only stronger!

Cass laughed happily, tossing the saddle over my back so it hung just over the small of my spine. I nickered with pleasure, feeling her tighten the buckles on it and make it perfectly snug against me. It was like wearing a back brace that was sculpted for my form, so comfortable on my form.

She followed this with a halter, fitting the bit into my mouth with a smile on her lips. I echoed her smile with one of my own as I chomped down on it, tasting the rich leather with a hint of drool from its previous wearers. That didn’t bother me—now I was wearing it, and I knew that Cass loved me more than anything else.

“Oh, you look perfect.” She smiled, sticking a foot into my right stirrup. With a smile and a laugh, she mounted me happily, wrapping both of her arms around my neck and snuggling her cheek against me.

I swished my tail from side to side eagerly, trotting us gently forward, out to the gate. To my immense pleasure, Cass didn’t stop me; instead kissing me lovingly and petting my neck again and again. “I love you so much, I really love you.” She breathed, pulling back to hold my reins. “Now let’s kick ass.”

And kick ass we did! I moved faster than I ever have in my life; as fast as a jet! It was incredible, amazing, wonderful! My hooves thudded at the ground; my frame thundering ahead like a bolt of lightning!

You can imagine the disappointment I felt when I realized we’d come in second. Apparently this race was a mixed-animals race, and there was a couple who’d TransFunned into a cheetah and a louse, which technically counted as an animal and rider.

I hung my head low as I walked back into the stalls, hoping that Cass didn’t feel as bad as I did. She dismounted me silently and I dipped my head even lower, ears flat with shame.

“You… You came in second. Sorry, but I only date winners, so it looks like you don’t earn me reversing your transformation.” Cass spoke harshly, breaking my heart. Then she hugged my muzzle tightly, sniggering. “Just kidding, you dummy! You got second! Second! And on your first race!”

She grinned and released my large head only so she could cover it in loving kisses. “I’m so proud of you, the only reason I didn’t tell you sooner is because I didn’t want to look crazy, celebrating for a close second! A close second! God, I want to ride you more; to feel that speed again! You’re perfect!”

I blushed and swished my tail with pleasure. Really? She was being serious? I neighed happily and place my head on her shoulder, licking her cheek with my big horsey tongue. How could I ever have doubted the love of my life! I beamed; then nudged her towards my flank, trying to get her to make good on that offer to ride me. And to my delight, she grinned back and slipped a foot in the stirrups, marking the start of a brilliant derby day.