...A gold ring. It was just a circle of metal with strange symbols engraved on it. You look at the clock and see that it's 7:30. You should get going in order to get to the park. You slip the ring on your finger and head to the park.
Once you get to the park you see your best friend Matt sitting on the edge of the fountain. You wave and say "Hi Matt."
"Hi Rick" Matt said. "You're right on time."
"You sent me the ring!?!" you asked. "I thought it was from a girl."
"Yes I did" Matt said. "Now I'll tell you what that ring is. What you have is one of the Rings of Transformation. I have the other one." Matt held up his hand to show you the ring on his finger. You see that it looked like the one you were wearing except that the symbols looked like they were inlaid with diamonds. "Mine is the master which means that anything I want to transform you into you will become. It even works on your clothes."
"What have you been smoking?" you asked. "You can't transform me."
"I'll prove it to you" Matt said. "I'll just change your clothes for right now. You're wearing a girl's diaper and that's the only thing you're wearing."
As soon as Matt finished speaking your clothes turned into something like mercury and flowed to your crotch and ass thickening what was already there. Once the mercury had formed the shape of a diaper it changed into a pink diaper with baby Minnie on them. You could only look at the diaper you were now wearing in shock. Then to embarrass you even further a couple walks by and looks at you weird. You can see them whispering to each other as they pass you. You had never been so embarrassed in your life, you just wanted to die.
"You see, I can transform you" Matt said. "I can transform you from anywhere on the planet. And in case you're thinking about taking the ring off you should know that you can't. I'm the only one who can take it off you. Well I should say the only one who can take it off is the one wearing the master ring. I may give it to somebody else at some point. You no doubt have figured out that the rings don't change reality. One more thing, you can't take this ring off my finger either. Now let's make you more appropriate for that diaper. You are a two year old girl wearing that diaper, a pink dress, pink socks, and white shoes with pink laces."
As Matt finished you felt a strange tingling encompass your entire body. You could even feel it in the diaper you were wearing. The world seemed to take on a silver color and you realize that your body has turned into the mercury like substance. You feel your dick and balls melt into your groin as a slit forms between your legs and new female organs form inside you. You notice everything getting bigger as you shrank. You look down at your body but you're unable to see it. You can feel the dress, socks, and shoes forming though. You can even feel your hair growing down to your shoulders. Once you are the size of a two year old girl your vision clears and the tingling fades.
You look down in shock at your body. You are wearing what Matt said you would be wearing. You didn't need to try to put your small pudgy hand down your diaper to check your sex, you knew that you were a girl. You try to ask Matt why he was doing this but all that came out was bay babble.
"I'm sure you're wondering why I'm doing this" Matt said. "I'm doing this because I want to control your life. These rings give me that control. While I can't make any mental changes or control your actions directly I can transform you into something inanimate or an animal if you don't do as I say. Now I'm going to pick you up and take you home with me. If you fight me I will transform you into an inanimate object that I can carry. I've already told my mom what I was doing and she's agreed to take care of you. Your parents have already been informed about this and they're glad to be rid of you. By now they're packing your things to give to Goodwill. Now let's go."
As Matt picks you up you start to cry silently. You don't fight him as there is no hope for you now. You have become his transformation toy to be transformed at his pleasure. You look at your small pudgy hand and see that the ring has shrunk to fit your finger.