Jason slowly raises his painful arm and flexes one of his new, now massive, biceps. The bicep feels heavy and full as if it has a huge pump from the gym magnified 100 times. He and Andy watch in disbelief as the huge, veiny bicep slowly rises into a perfect round ball. It feels as if it will rip through the tight skin around it as Jason lightly touches it with his other hand. "Look at me!" Jason says, unable to believe what he's seeing and feeling. "Look at this fucking bicep!"

Andy gives a groan of ecstasy and says quietly, "That body's fucking incredible Jase. Fuck me some more while you flex it".

Jason starts to slowly fuck Andy again and carefully lifts his other arm painfully flexing it into another huge ball of muscle.

"Oh fuck!" Andy screams as loud as his tired body will let him, at the sight of Jason flexing both of his biceps. "Fuck the shit out of me with that muscle body!"

Jason speeds up his thrusts and starts to pound his dick into Andy's skinny body as he unflexes and flexes his biceps over and over watching in disbelief as the huge muscles rise into round peaks of hard muscle. As much as he had prepared and dreamed for this day, it is still unreal to Jason how enormous, hard and perfectly peaked his biceps had become. "Look at 'em Andy! Look at these rock hard mountains of muscle! You wouldn't believe how they feel! It's incredible!" Jason proclaims as he drives his dick harder into Andy's ass.

"They look so fucking good!" Andy moans, "Fuck me harder with your muscle body"

Jason puts his arms down at his sides and starts to flex his pecs, the pain in the swollen muscles is unbearable. He looks down as veins and striations etch across the thick muscles. The awesome sight propels him through the pain into a "most muscular" pose.

"Fuck!" Andy screams. "Look at those fucking pecs we've made, my muscles and your muscles both crammed together into your huge pecs! Fuck me harder with that body!"

Jason looks down beyond his pecs at the rest of his body. His abs, now tight and well defined undulate and flex with each thrust his dick makes into Andy's body. His thighs, thick, muscular and defined, still covered with veins trying to force the last bit of power into his quads, work in unison with his abs to drive his dick hard into Andy's ass. "Look at me!" Jason screams in disbelief. "I'm HUGE! I have MUSCLE! I AM muscle!" Jason can feel his balls starting to load his dick with cum. He flexes a bicep again and wraps his other hand over the top of it, flexing the huge muscle as hard as he can. The bicep tightens under his hand, rising tall and round. He rubs his hand over the hard ball of muscle feeling the veins...and fibers...and striations under his silky smooth, tight skin. He rams his dick harder into Andy's ass.

Andy lets out a satisfied groan of ecstasy as he watches Jason flex and feel his baseball-like muscle.

The feeling and sight of his own fully flexed bicep is more than Jason can fathom. It feels like the tightest, fullest, most painful pump he has ever imagined having. He notices how his hand barely fits around the huge, mountainous muscle. Jason slams his dick deep in Andy's ass and feels cum shoot out as he gropes the unbelievable new ball of rock rising from his arm. His dick shoots for what seems an eternity as he flexes, gropes and explores every inch of the new muscle packed into his body.

Jason's body, wracked with an incredible pumped pain - now a good 35 pounds heavier - collapses onto Andy's frail body. Jason knows he will help Andy build his body back into what it was…and more. Jason knows he is eternally grateful to Andy as his "first"…as a feeling deep within him already starts to yearn for more muscle.... •