Sam plucked an apple from a nearby tree, inspected it for blemishes, and wiped it on her shirt. Before taking a bite though, the thought struck her that it could be cursed in some way, and it might not be the best plan to simply eat it. Instead, she offered it to Cinnamon, who after giving it a good sniff, snatched it from her head, munching it and swallowing it whole. He gave what seemed like an approving whinny, and didn't seem to start turning to stone or anything like that. So, feeling safe, she grabbed a second apple, taking a few bites herself. Suddenly she felt very very dizzy.
Sam dropped her katana to the ground, and slumping forward onto the horse's neck, and then, somehow, she found herself sliding forward. It was a strange feeling indeed, almost like an out of body experience, and suddenly she couldn't feel her legs. Then just as suddenly, she could... but they were in the wrong place, and also the right place? Somewhat? There was also a sudden heavy weight on her back. And the sound of a horse absolutely screaming.
Sam panicked, trying to dash forward, and not having a real handle on her new body, ended up rearing back and tossing poor Cinnamon to the ground. As Sam turned to see, it became clear what happened. The top of her body was on Cinnamon's now, making her a centaur, apparently, while the former horse was... the leftovers. Just the head and neck of a horse, attached to a woman's hips and legs, rolling on the ground and screaming.
Sam reached down to try and help, but found she couldn't bend her torso more than 90 degrees, and her new legs were far too long relative to her arms to reach the ground. Thinking fast, she gestured towards the sword, and spoke in a soothing voice, hoping the former horse could hand it to her, somehow. Luckily, if not intentionally, the flailing creature managed to grab the hilt in its teeth, and much like Sam had earlier, transformed into a gorgeous redheaded human woman. Completely naked at that. It was at this time that Sam became acutely aware that her lower body was that of a male horse, but frankly being so well hung just made this even more awkward, as Sam was now faced with a horse-turned human who was quite upset and holding a sword.