"Fine." Said Tony. "Just so you can see it works. But... here's a deal. I'll try this if you try... this." Tony said as he pulled out the exact opposite of his own powder. Ben looked it over "Penis shrinking powder? I guarentee it won't work." he said. Tony laughed "How much are you willing to bet?". Ben looked at him smugly "How about all 9 of my manly inches?". Tony grinned. They each popped open their packets and swallowed the contents.
Ben licked his lips. "Tastes like a pixie stick." he said. Tony nodded in agreement. Nothing happened for a few moments, to which Ben said snidely "See?" but then it began. Tony looked down at his crotch as it tingled. A small bulge began to form, growing larger and larger. His jeans were getting tight around it "Whoa! Check this out Ben!" He said, pointing. Ben went wide eyed as the lump swelled larger and larger. Seams were popping around it, the zipper was groaning, and in a moment it burst. Tony's now 15 inch flaccid dick sprung forward and swung from side to side, still swelling. It was inhuman, 17, 20, 25 inches. It was hanging lower and lower, thick as one of Tony's muscular legs. Soon it was hanging down to the floor, it's very tip brushing the cool floor of the shop as it swung. It was still growing! 40 inches, 45.... 52 whopping inches!
"See Ben! It worked!" Tony said, taunting... then he realized it... if his worked, would Ben's? Tony had gone from 4 inches to 52... what would happen to Ben? Ben looked down at his own bulge, which was always evident, but it began to deflate. The crotch of his jeans becoming looser and looser. He quickly unzipped them and pulled down his underwear. His dick growing erect, which normall would land him at 12 inches, was just under 10. It was shrinking quicker and quicker, the skin becoming smooth, veins dissappearing, it became thinner and shorter, still proportioned as it had once been. His erection size was now shorter than his flaccid size on a cold day. It was 6 inches, then 5, 4 inches... He grabbed at it, only for it to fall to 3 inches. "Stop!" he shouted aloud. The powder had it's own agenda though. 2 inches... 1 inch, a half of an inch, an eigth, and then it was so small it was hard to see. Then it simply dissappeared. Ben stood there, smooth crotched with his oversized balls still hanging out. Tony gaped, taking his mind off his own 4 foot cock.