Nick was staring at the white speedo in his hands while Riley started to take off his clothing. He realized that his friend was way more confident than him because Riley didn't mind he was getting nude in front of him. Of course, they both were just 11 years old without any trace of puberty yet, despite Nick noticed that Riley's dick seemed a little bit smaller than him.
Nick decided to follow him and he started to undress, although he was doing it slowly because he's still a little shy. Meanwhile, Riley was already putting the speedo through his legs, intentionally ignoring it seems too big for him. He just wanna go to some free shows and look cool to his friend. In fact, he always tried to look confident in front of everyone because he was trying to hide all his insecurities. He was short in practically every aspect of his body, he wasn't a very good student nor very athletic. He even wasn't very good at videogames.
Riley continuously tried to prove to himself he didn't care too much about his lack of talent, so he usually acted very friendly and confident. He had seen all the people wearing speedos like these, so he didn't want to be different from them. However, when the blue fabric was around his waist, it was definitely obvious that it was too big for him. His noodle-like legs were too thin that he can still through the holes and something similar was happening with his waist.
"Don't you think these are a little too big for us?" Nick asked him as he watched his friend struggling with his blue speedo. He was still wearing his tighty whities, so his own speedos were on his hands. He didn't want to embarrass himself by wearing something that's obviously too big for him. "Maybe these ones are for adults. I'm going to look if there are other speedos."
"There aren't. These were the only ones in the drawers." Riley said as he uselessly tried to adjust his speedo. "I guess you're right... I'm going to take it off. We can hangout with our own clothing and look for some free shows..." Riley started to pull down the blue clothing when something weird started to happen. His stomach began to make noises and he suddenly burped like a champion.
Then he kneeled in pain grunting, and groaning loudly, squirming and holding his stomach as if he's going to puke in any second. He groaned again, then his eyes widened as he belched again and again, and finally he farted very loudly. After that, his whole body started to pop and creak. making odd squelching noises as his feet snapped, grew and got meatier. He was yelping and groaning as his body was thrust through a brutal growth spurt, lengthening, widening, becoming tall and buff, filling in with several layers of muscle and fat.
Riley started to sweat, as body hair started to fill over his legs, up his now meaty thighs, into his now skintight blue speedo, then up his abs and his chest turned red and itchy. He scratched desperately at it while a pelt of hair grew in and dampened. Finally with a desperate whimpering groan, he collapsed, panting, flat on his back, now a 6'11" tall behemoth, bear-like complexion that definitely doesn't look like a kid at all.
Nick looked down shocked while he curiously rubbed his hand through his friend's vast chest pelt. He still can't believe what he just saw and immediately threw his speedo away in fear that it could happen to him too if he wears it. Riley looked exceptionally big in every department, including the ones he was lacking off a moment ago. The former loose speedo now seemed obscenely tight without enough fabric to cover Riley's new nest of pubes. Nick felt intimidated just by looking at Riley's powerful legs and arms.
A few minutes later, Riley started to recover himself. Everything was spinning in his head and he felt like if he was wearing a heavy sumo suit. However, despite he can feel it's heavy, he felt strong enough to move it. He put a foot and the floor and wondered why it felt so different and weird. When he managed to stand up, he looked around like if he was waking up from a dream and noticed that Nick was staring at him open mouthed. He was still too dizzy to realize that his friend seemed shorter and instead he just smiled at him. "So, how do I look?"