Jim stood there at the food court and thought a moment. He decided that he really wanted to try out the balloon on himself, but not here. He left the mall and rode his bike home. When he entered his house, he called out to see if anyone was around. No one answered. He was alone. Perfect, they must all be out at one of his sister’s soccer games or something.
Jim ran up to his room, shut the door and closed the drapes. Even in an empty house, he wanted to keep this as private as possible. He pulled out the balloon and considered what to try changing first. The old man in the shop had already played around with his height. Maybe Jim would just try a single body part.
Suddenly it hit him, as his eyes drifted down to his crotch. At 12, he was just starting to enter puberty, and was starting to discover new feelings that would occur from his penis. He'd often wondered what it would feel like if it were bigger. Now he didn't have to just wonder... he held the balloon that would let him experience it! Jim considered taking off his pants before he started this experiment, but decided against it. Keeping his pants on would allow him to feel what it was like, he reasoned. Also, if anyone came into the room, it wasn't immediately obvious.
"Control the size of my penis... and my balls" Jim said, remembering to include his balls. "Just a few breaths" he said, and bringing the balloon to his lips, he blew a breath into the balloon.
Immediately he felt his underwear seem to shrink around his cock, the material feeling tighter like it had shrunk in the wash. However, as Jim walked around the room he could feel that his crotch was actually slightly heavier. "Is this what it feels like?" he wondered. Bringing the balloon to his lips again, he blew another breath into the balloon.
Now his crotch was definitely heavier. Looking in the mirror, Jim could see a small bubble in the front of his jeans, where there normally wasn't one. He smiled and strutted, watching as his new bulge jiggled as he walked.
Forgetting he didn't want to blow more than a few breaths, Jim blew into the balloon again. This time he actually got to watch as the bubble in his jeans seemed to expand, sticking out more and also widening a bit as the jeans started to stretch to contain Jim's manhood.
Jim blew again. His crotch started to feel incredibly heavy at this point! The bulge in his jeans also swelled even larger, to the point where it looked like Jim had stuffed a basketball into his crotch.
Jim was curious just how much his cock had grown. As he walked through the house, he was glad nobody else was home... he would surely have been questioned about the fairly large bulge in his pants. He managed to get the ruler and walk back to his room successfully. Once he got back, he pulled down his jeans and underwear.
His monster cock flopped out, hanging over halfway to his knees. Jim gasped when he saw the end of his cock went past the full length of the ruler. He had over a foot long, and it was still completely soft! He knew boys didn't have a tool this big naturally. Sighing, he began to release air from the balloon, stopping when it reached about 6 inches soft. That was a manageable, but still large size. "Release" he said, satisfied.