Dustin eyed the bench outside the department store, waiting for someone to use it. Sure enough, eventually another boy walked along and sat down. He looked to be about 12 years old and mildly athletic. He was wearing basketball shorts. Dustin looked through the boy's shorts and stifled a laugh when he realized the boy was going commando, but only because his cock was laughably tiny - just an inch and a half. Well we can fix that, Dustin thought. And began staring.
At first it appeared that nothing was happening, but Dustin could see inside the boy's shorts and knew better. It began to gain length, slowly at first but then faster. 2 inches... 3 inches... 4 inches... then the boy's balls suddenly kick-started into action, swelling from almost nothing to the size of ping pong balls. 5 inches, and it had reached the average size for a teen. But Dustin kept going. The boy's cock began to thicken and length at 6 inches. At 7 inches, it began to sliver down the boy's leg. 8 inches passed, then the boy's balls experienced another sudden jump in size, growing to the size of large eggs. Then the boy hit 9 inches. Dustin finally stopped staring when the boy's cock hit 10 inches in length. The boy looked down wondering why his shorts were so tight all of a sudden, and gasped when he saw the outline of a huge cock in his shorts.