"Fuck dude, what are you doing?!"
Roy put both hands on James' chest, and pushed him away harder than necessary. James fell back, losing his footing and tumbling to the ground. He didn't get up.
"Dude? You OK?" Roy nudged him with one foot. "Come on..."
He squatted down to check James' head. "Oh man..." Roy moaned. His cock had now squeezed past his left knee, trapped beneath the straining wetsuit. A shallow ridge appeared, just below the knee, where the helmet of his now-huge endowment pressed out prominently. Roy squeezed himself into a less-painful position and checked out the prone James.
Sure enough, James was unconscious. There wasn't any blood, but hitting his head on the rocks had knocked him out cold. He was still breathing, at least...
Roy stood and shifted again uncomfortably. The pressure was just too much. He looked around, to confirm no one could see, and unzipped his suit. He peeled the rubber off his lean, muscular chest and down below his aching groin. With both hands he reached into the left leg and hauled out his now-massive python. Carefully, he scooped out his balls as well, letting the blond softballs dangle heavily. With his newly-huge genitals finally released into the air, he breathed a long sigh of relief.
He gazed at his cock in wonder. How had this happened? He used both hands to support it -- he was still mostly soft, but it was already over than 9 inches long! He traced one of the thin blue vein that ran along its length, and he shook at the feeling of those new, pleasurable inches. He circled his thumb and index finger around it, but couldn't get the fingers to touch. With two hands he circled it, as the monster grew heavier and harder at his touch. When he opened his eyes, a 13-inch erection stared back at him. And it seemed like it was still growing!
Roy looked down and noticed James still laying against the rock. He'd tumbled onto his chest, with his ass poked up in the air and the shorts pulled tight against it to show the crease between the two globes. "Hmm..." thought Roy, still slowly jerking up and down his huge erection. "The guy *is* gay..."
Then Roy noticed something else. That little contraption had fallen out of James' pocket. "Maybe something on the guy's PDA can explain what he happened to me..."