Alison watched with some fascination as Joy's features changed. She kept the oversized bust that she'd had, and the size of her hips hadn't changed at all, but what DID change was... well, almost as dramatic in their own ways.
In disguise, Jon still had body hair. Some of the chest hair had been eliminated by the development of breasts, but much of it on her back, stomach, and legs had remained. That all quickly fell out, followed by the facial hair that had remained behind.
Joy's leg's thinned out a bit, though the size of her feet remained the same, and then her torso shortened just a bit as her stomach, not constrained to a specific size by her blouse, contracted a bit. Joy's arms became smaller, more slender and feminine, leaving only her fingernails unchanged in that department, and finally her neck and face became thinner, more feminine than they had been before.
Finally, Joy looked at Alison through appropriately feminine eyes, pouting with her appropriately feminine lips, "Alison!" She complained with a new, higher voice that more closely matched her new swimsuit-girl figure, "Warn me next time!"
Alison cringed. That would happen to her!?? Oh well, being a hot girl was better than being a freak, and since she couldn't just turn back into a boy... "Okay, I'm warning you that I'm going to order you to tell me to do the same. Now tell me to do what I told you to do."
Joy blinked, "Okay then, Alison, Change the rest of your appearance to match what Karyn changed you to."