After a little thinking, John decided that he would put the collar on his annoying neighbor, Michael. He was a 11 year old boy who lives next door and his room's window was right in front of John's. Michael likes to tease John and he usually jumped through the windows to make prank on him. John remembered once time when Michael put his hamster in John's face when he was sleeping and when John noticed it he started to scream. John smiled deviously as he looked through his window and noticed that Michael's window was open. It's time for some revenge.
John peeked into Michael' room. It was Saturday morning, so Michael was laying on his bed, wearing only his briefs, fast asleep. John crept over to his neighbor's sleeping form, slowly inching the collar forward, before slipping it around Michael's neck. As John clicked the buckle, Michael began to stir. John quickly sneaked out of the room. Michael sat up slowly and looked around. Confused, he raised his hand to the collar.
"What the hell?" Michael said. John decided that now was a good time to look out his window. He smiled at the boy, feigning ignorance.
"Hey Michael." He said. Michael looked at John for a moment, then his body began changing. Michael's hairless chest became to grow hair. John thought the pet collar will turn Michael into a dog or so but those hairs didn't look like fur at all. Also, Michael's chest was getting bigger and stronger.
Michael stood up and John was surprised to see that he was taller. Too much for a 11 year old kid. Additionally, he didn't stand up straight. Michael stood in a pose that reminded John of a begging puppy. He opened his mouth startled.
"What's happening to me?" asked Michael.
"I don't know." John said, "How do you feel?"
Michael said, "I feel weird. I feel like I'm two people. We are both Michael."
John became nervous. "What do you mean?"
Michael said, "We are Michael. One of us is a scared kid and one of us is your pet slave but we are Michael. You did this to us!"
John grinned, "Don't be mad. It's my little revenge. You owe it to me!"
Michael said, "We don't know if we're mad. We are confused." He looked at his body as it still was growing up. "Your pet slave wishes to get rid of this constriction, what do you call it, underwear but the kid wants to put on more constriction. What should we do?"
John asked, "If I tell you to remove your briefs, would you obey me?"
Michael removed his underwear. From head to foot, he had got a lot of hair and muscles. He now looked like a young man in his mid twenties instead of a preteen boy, his adult dick and balls were on full display covered with a big amount of pubes that had recently appeared in there.
John thought for a moment. He hadn't thought this through. He had thought it was just a joke but now he realized he could get in trouble if people saw Michael like this. "I want you back."
Michael stood up straight and seemed to get smaller. His recently grown body hair also receded. He stooped down to retrieve his briefs and then a pair of jeans and a shirt. As he dressed he said, "That wasn't funny John!! I was scared as hell!"
John asked, "Are you mad?"
Michael said, "I am... But... I don't know why but I'm not at the same time. Maybe it's this collar. I want to run away from you but I'm still your pet, so I will stay."
John got inspired, "Strip."
Michael stripped again but now as a kid. "Are you a pedophile? Why do you want to see me naked? This isn't right."
John answered, "You're right. Maybe you should turn back to that hot body you had a moment ago." After saying that, Michael started to grow up very fast until he was a hairy strong man again. "This is fun,
I mean, this power over you. This is better than I expected. You can act like my neighbor so no one gets suspicious but you're still my pet slave."
John jumped through the window to take a closer look at hunk in front of him. Then he took hold of Michael's hairy balls. "I've got you by the balls little brat."
Michael answered, "Yes you do. Please don't do this. Please let go and let me turn back to my original age."
John asked, "Is that how my pet feels?"
Michael said, "It's how a very scared kid feels. If I wasn't your pet I will be crying like a baby. Your pet wants to play, too discover what this body can do for his master."