It was a dull Saturday morning in July, about 10am, and it was already starting to get warm outside. He looked over his thin teenage body in the full-length mirror on his closet door and sighed. At 5'4", he was at puny 95 pounds. He was a toothpick. And at age 15, that was sad. He had always wanted to get big, lift weights like the other kids at his old school did, but his parents never let him.

Just when he thought he got them to think that it would be a good idea for him to start lifting weights to protect and defend himself from the bullies at school, both his parents died in a horrible plane crash. He ended up getting sent to his Uncle Brad's to live in San Diego. He liked it there -- lots of hot young jocks parading around in low-riding cargo shorts, almost to the point of their ass-crack showing, driving around their Jeeps with the tops off, as well as the tops on themselves. All that young flesh soaking up the rays of the burning summer sun, darkening their chiseled physiques. It made his mouth water.

He knew he was gay since he was 10, when a neighbor, Josh and him fooled around when Josh babysat him. He enjoyed it alot, and misses Josh alot. He sometimes even snuck over to his house in the middle of the night and climbed through Josh's window when he needed his little cock sucked, or if Josh needed to plow some ass. Zack loved to have his ass rammed by a thick cut cock. It hurt like hell the first few times, but he got used to it after awhile. He even returned the favor a few times, it was the most pleasurable sensation he had ever experienced.

Now he is stuck living with his Uncle Brad. He misses his parents alot, so he is hoping that he can start anew in California. First thing he is going to do, is to convince his scientist uncle to get him a weight set so he can start working out. He slipped in some cargo shorts and put on a short-sleeve button-up plaid shirt and trotted downstairs to the kitchen to see what Brad had cooking for breakfast. He was nowhere to be found. There was a crash and cursing in the basement below the kitchen. He was working in his lab. He pushed the door open slowly.

"Uncle Brad? Y'ok?"

"Yes, yes, Zack, I'm alright. Come on down if you want."

The boy went down the stairs to see what his uncle was up to today. "So what are your plans of making the world a better place today?" he joked.

Brad was in the utility room in the back. "Ha ha, very funny." Brad was only 25, but a real brainiac--and hot to boot. He was only 5'8" in height, short dusty blond hair and a lean body. Zack thought his uncle looked real sexy, even in his lab coat. He always thought his uncle should go into the modeling biz, but he loves his science.

Zack was real thirsty and forgot to grab a glass of water while he was upstairs. He was about to get one when he noticed a glass of clear liquid on the bench. "Is it okay if I have some of your water?" he called out.

There was another crash. "What's that, Zack? Yah, sure."

He reached for the glass and gulped it down as Brad came out of the back room, and stopped in total shock. "Oh my god, you did not get that off of my work bench, did you?"

Zack finished it off, licked his lips and put the glass back down on the bench. "Yah...is there a problem? Wow, that was the sweetest tasting water I ever had. Real different from Colorado water."

Brad's eyes were wide in horror. "Do you feel ok, Zack?"

"Yah, why shouldn't I?"

"That was not water. That was one of my experiments I have been working on for the past few months."

"Really? I feel ..." The room started to spin. "Woah."

Brad put his hand on the young boy's shoulder. "Now take it easy. I may have to call poison control. Let's get you over to the couch." He tried to coax his nephew but his feet were firmly planted to the concrete floor.

Zack started to sway forward and backward in place. "What was that stuff, Unc? It feels like I am burning inside now. All over. My legs, arms, shoulders, stomach..." Then he doubled over in pain. "Ow!"

Brad held onto his nephew. "Take it easy. I have no idea how it will feel, but you are going to feel some changes."

The teen let out a grunt -- a very low grunt, almost animalistic in nature. He looked at his hands, they were trembling. His body began to contort under Brad's hands. He could feel the muscle fibers inside his nephew's body mutate and enlarge.

Zack was growing.

Soon the teen's body began to fill the loose-fitting shirt. Huge, rounded delts took every square centimeter of space inside the sleeves. His skin began to darken, and tighten, having a difficult time being able to adjust to this sudden change. Veins were erupting all over his taut skin, and the checkerboard pattern on the shirt began to buldge, as his body is screaming to be released from the confides of the clothes.

His body was contorting, and Zack fell to the floor. He was sweating heavily, the aroma of teen sweat permiated thoughout the lab. The boy let out a deep growl, of pure ectasty. He smiled as his shirt began to rip, while his traps began to stretch the shirt beyond its confides. His arms shot outward, as his back began to form a thick v-shape. Huge balls of muscle filled the arms of the shirt and started to make a slow, sexy ripping sound. His chest heaved deeply, as the front of the shirt was beyond the point of holding the body any longer, and buttons started to fly, and his massive back was causing the shirt to rip down the center

Zack was able to sit up. He grabbed the front of his shirt the best he could and ripped it open with a deep snarl. "Grr...oh yah!" as the tattered fabric fell to the floor. Now his legs were begging to be let out of the shorts, the loose-fitting clothing was now way too tight, and was cramping his now erect dick.

Brad watched as his young nephew's body transformed from a skinny, scawny boy to a young bodybuilder. His body rippled with muscles everywhere. He was very tuned on by this. The shorts began to rip, and Zack tore them off with one swift movement to expose his naked body to the air. His cock, which used to be only four inches hard, was now a thick, 8 inch cut piece of meat.

The teen tried to put his arms to his sides, but his lats flared out so wide, his arms stuck out. Brad watched as the boy strutted over to the mirror on the wall.

"Holy fuck! I'm HOT!" he said, in a deep voice. Even his voice had been changed by the formula. "I look like I should be on one of those teen bodybuiler sites, I would fuckin' blow them out of the water!" Even his confidence has been increased from the formula. He no longer hated himself. He wanted to have sex with himself. He turned around to his uncle, to see him rubbing his crotch. "You like what you see, huh, Unc?" He did a most muscular pose, causing his engorged body to swell, as some of the muscles were still growing. "Well then, come suck off your musclebound nephew's new cock!"

Brad walked over to Zack, bent down and kissed his nephew, inserting his tounge deep into the the teen's mouth. He worked his way down the boy's massive, striated chest, down his 8-pack abdominals, then to the trobbing love muscle. The boy held his uncle's head as he worked on giving him total pleasure.

It did not take him long to cum, since the experience of growing to the massive hulk he was now did a lot for him, and exploded into Brad's mouth. He knelt down and kissed his uncle deeply and forcefully. "Measure me," he hissed.

Brad went and got a measuring tape, and Zack began to flex his bicep. He felt so sexy, so powerful. There was a scale in the corner of the room. He was amazed at the results.

"Fucking a! I weigh 190 pounds!"

Brad walked up to the boy. "That is alot better results than what I had estimated the formula would do. I guessed it would put on around 50-60 pounds tops, but not almost 100. Here, put out your arm." He measured the huge cannonball, viens criss-crossing all over the dark skin, another effect that he put into the formula - a natural tan. "18 inches. Now, your waist. Still 28 inches. Nice. Now relax your chest." Zack's chest was pure perfection. Two huge pillows, with a deep cut clearly defining the two. "48 inches!"

Hearing these massive measurements, Zack was hard again. "I have a favor to ask of you Brad," the muscle boy asked.

"Anything, stud."

"Mix up another batch of that formula. You have to experience the growth. I want to see you grow as you got to see me." •