Shortly after the previous "victim" left, a kid around the age of 11 walked in. He was pretty tall, but otherwise fairly average for his age. He slipped off his underwear and pulled on some briefs. Right as he did, Dustin began to stare at him.
“Ummm” the boy groaned, as he began to feel his cock expand. It began to elongate from its previous 2 inch soft size. Dustin was trying so hard not to laugh at the boy's high pitched moan as he saw the front of his briefs begin to bulge out just slightly. The boy kept moaning and his cock kept growing. It was now about 5 inches soft and was also gaining thickness as well.
As the boy kept moaning, the briefs began to bulge out more, struggling to contain the boy's now-sizable endowment. By now his cock was pushing 7 inches and his balls had also swollen to almost the size of tennis balls. But the briefs didn't seem to be straining! Instead the fabric was stretching comfortably to hold the boy's large genitals - the clothes would modify themselves so that they would never rip!
Ty's magic was working well, but it was starting to look ridiculous. The boy passed double digits, with a 10 inch cock and balls the size of softballs. By now the briefs had deformed so much that if the boy had taken them off, a huge pouch in the front had been created, but at the moment the pouch was filled completely and still growing to contain the boy's continually enlarging penis.
Dustin just couldn't stop staring, the sight was strange - a 12 year old with one inch of his cock for every year of his age - and as Dustin watched, his underwear kept swelling out, keeping pace with his growth so that it would never rip. Dustin finally quit staring when the boy's cock had reached 14 inches long!