Ty walked back and forth, admiring his massive, 6'6" tall, 350-pound musclebody in the mirror. He reached down to pat the bulging Coach-jockstrap, holding Jim, Tom, and Rob inside it. "Sweet..." Ty purred happily, grinning. He turned around to see Dustin. "Thanks for the assist, Dustin," Ty said, even as he stripped his brother of the powers he'd given him. "As your reward, why don't you take these guys for a spin? You've earned it!" Ty pulled off the jockstrap, his body reverting quickly to its normal state. The jockstrap looked quite ordinary now, and Dustin took hold of it gingerly. "Go on!" Ty encouraged.
Dustin grinned back, and then pulled off his pants and underwear. He slowly slid the jockstrap on. It was big on his body, but as soon as he got it up to his waist, the changes began.
Dustin's balls began to swell, filling with Tom and Rob, who looked out at the white fabric of their jockstrap prison. Next, Dustin's cock grew to a foot long monster, packed with muscle, looking like Jim. Finally, Dustin's body exploded with muscle and size of its own, his height increasing dramatically, until he was six and a half feet tall, his muscles bloating with power, his body coming in at a hefty 350 pounds, ripped to the bone, hard and strong. His shirt was ripped from his body in the process, torn to shreds as he'd forgotten to take it off first. Dustin lifted up his big arms and flexed in the mirror, grinning as he watched the giant biceps roll and swell.
"Thanks, Ty!" Dustin bellowed, his voice deeper now.
Ty laughed in reply. "No problem, Dustin! Have fun! With Jim there, you can give or take size or strength to or from another man!"
"Oh yeah..." Dustin growled, a touch of malice in his voice. "I can think of some people that need to be taken down a peg or three..." He chuckled evilly. "Say Ty, suppose you can get me some clothes though? Mine don't fit any more!"
Ty laughed again, and in an instant Dustin was dressed, as he had been before, except that all his clothes hugged his huge body as if they were perfectly tailored, the shoes and pants much bigger, as was the repaired shirt. Dustin's underwear lay to the side, still small, and unnecessary.
"There ya go, now have some fun!" Ty grinned.
Dustin flashed a smile back. "I will. Believe me, I will!" The young hulk then turned toward the door and headed out, his mind filled with thoughts of...