Ty had experimented with the ring enough that he was comfortable with its power, and now he was ready to take a serious plunge with it. He was eager to complete the changes he had in mind, but he felt it would be safer and easier to make several smaller wishes.
First, he wished that his foster parents would love him and Mei no matter what, and would always reconise who they were regardless of their changes. (But he made sure they wouldn't see Mei as Dustin, and that they would accept the two's forms.)
His second wish was that he would become a smaller than average teenage girl. He also wished that he would think like a teenage girl, but still be himself. This meant that he'd act much more feminine and have all the knowledge a teenage girl would have, but he would still have mostly the same personality and thoughts. He waited a moment and the wish started to take effect, shrinking him down to 4'6" and around 60-70 pounds (very frail looking, I'm not sure about the weight), turning his hair long, deep brown, and tying it into a ponytail, shifting his bones and muscles into feminine shape (but not too curvy), and then made his clothes disappear for the final changes. Ty and Mei watched as Ty's penis vanished quickly with a painful tug, being pulled inside his body, then being slowly replaced by the female sex organs. Ty was now panting, partly in pain, partly in pleasure, as he (now she) layed back on the bed. The final changes of the transformation weren't very spectacular, all of Ty's body hair fell off (even at the groan) and a pair of A-cup breasts grew quickly.
Ty couldn't help hi-- herself as she took a quick break from the changes to grope her breasts, which were firm and soft, and probe a finger into her slit, which took a little while to get wet. Ty had become a small fourteen year old girl.
Ty finally came back to her senses after a couple minutes. A couple minutes which had made Mei start probing her own slit and moaning. Ty let her go on until she came, then wished that the both of them were completely clean and naked.
Wish number four (well, five) was to put both girls into snug teen diapers and pink t-shirts. Mei smiled at this and was visibly excited. Ty smiled back and moved on to her next wish.
Ty wished that she and Mei couldn't control their bladders or bowels, as well as wishing that everyone remembered them that way, but accepted it at least to some degree, and that their parents or the school nurse changes them whenever they've messed their diapers.
Following this wish, Ty wished that both the girls' rooms looked like average teenage girls' rooms, with the exception that both would have a changing table with infinite baby supplies for the Ty or Mei (depending on who's staying in which room), and would their closets would be filled with whatever clothes and baby items they want when they go to open it (They can close the closets and re-open them for different clothes).
Mei practically threw herself at Ty and hugged half the life out of her. "I love you! I love you! I love you!" Was all she kept saying, over and over, for about five minutes. She eventually calmed down and released Ty, letting the tiny girl breathe. (Ty said all those wishes out loud, I'm just terrible at writing dialog.)
"I'm glad you like it, Mei." Ty managed to say between gasping breathes.
Seeing how happy Mei was, Ty couldn't resists giving her another gift. She wished Mei had complete free will, and had all of Mei's and Dustin's memories.
Mei stopped immediately and blushed. "T-ty? Um... You... You won't tell anyone about all of this, will you...?"
Ty looked a little sad, but he knew this would make Dustin happiest in the long run. "Mei... Er, Dustin. Everyone knows, but don't worry, they all accept you. I know you're happier as Mei, and I promise I won't do anything to make your life miserable. We're sisters now, and friends, right?"
Mei looked down for a moment, then looked into Ty's eyes. "You promise? Do you promise we'll be sisters, and no one will hate us, forever? We'll be friends?"
Ty smiled. "I can't guarantee everyone will like us, but I promise no one will hate us and we'll be sisters and friends forever."
Mei fell into Ty's arms, crying tears of joy. Ty rocked her and held her close until she calmed down and smiled again.
"So... What do we do now?" Mei wiped the tears off her face and smiled.
"What do you want to do?"