As the afterglow from his monumental orgasm faded, the first thing Raijin felt was a dull, persistant ache all through his body. He backed away across the kitchen until he could see as much of his body as possible in the formerly full-sized mirror next to the door. It seemed like he wasn't growing any taller at this point. He estimated he was 6' 6" now. Despite growing 6 inches, he didn't think his body looked much different aside from his longer limbs, somewhat broader shoulders, and his new huge endowment. His muscles must have grown in proportion along with his height. He gave his arms and pecs a quick experimental flex. His large yet well-balanced build was still on display in the mirror. That quickly changed as a painful pulse suddenly rippled through Raijin's body.
"Ow! Ugh," he grunted through clenched teeth. "Now what?"
The pain pulsed again, and he doubled over gripping his midsection. His arms, legs, and abs all throbbed in time with the pulses. Eventually, the pains began to ease into gentle ache not unlike the pump he felt after working out, and he felt it spread out to all of his muscles.
He straightened back up, and he was first drawn to his abs. It seemed like they were done changing, but they had grown into a huge, deeply-cut 8-pack. His entire midsection was completely shredded and felt extremely powerful. Two large veins reached up from his groin over his lowest pair of abs. He twisted side to side to see his obliques and serratus. He noticed his forearms in the mirror as he did. He couldn't feel the throbbing in them or his legs anymore. A network of veins had popped up over his thick, tight forearms as they had grown. He checked out his calves. They had also swelled larger. Both muscles were clearly visible bunching up high and thick as he flexed his leg from many angles. They were easily visible on either side of his shins as he checked them out in the mirror.
Raijin's focus on his legs was broken when the throbbing in the rest of his body suddenly intensified. Each pulse made him feel tighter and more pumped, and periodically he would get hit with an especially intense wave like a massive cramp. He was covered in sweat again, and veins stood out all over his body only to be pushed out more and more as he felt his growth continue.
He watched his big thighs swell larger. His quads bulged bigger as the separations between them sharpened. The most prominent muscles grew into huge, striated teardrops resting heavily above his kneecaps. Rather than growing extremely broad, his upper legs were growing thicker as his hamstringing rounded out in the rear. A big throb pushed another shredded inch into each muscle and sent veins pulsing to the surface. He reached back and felt his ass as it seemed to reach unreal proportions. It had grown tremendously thick and high on his waist. Each glute was rock hard and felt almost like half a globe if globes were ridged with steel cables. He flexed them experimentally, and he grinned as he found he could make them bounce and dance a little like his pecs.
Speaking of pecs, he turned his attention to his upper body which had been just as busy growing. Checking his form in the mirror, he noticed his lats now burst abruptly outward from high up his midscetion to meet his broad shoulders giving him a coveted "Y-shaped" torso. Thick traps curved gracefully from his neck into his shoulders as well. To either side, his biceps and triceps had added a couple of inches to his arms. He brought them up into a double bi pose. He marvelled at not just the height of his arms, but the thickness of his bis and tris. They had to be nearing 20 inches at this point, a size he had always dreamed of achieving. His arms were engorged by another big cramp, and through the pain, he watched them stretch even bigger. No doubt about them breaking 20 inches now! He lowered them and traced the massive vein across the head of one bicep up to his tightening delts. They were huge, round cannonballs of power capping out the corners of his frame. He watched as one pulse of growth created slight red stretch marks across their front which faded just in time for the next pulse to bring more. Finally, he admired the hills of muscle his pectorals were becoming. Instead of taking up much more room on his torso, they appeared to be focusing on growing thicker. They now swelled many inches outward from his collarbone and tucked tightly inward above his abs. He reached up and felt their taut, striated expanse pulse now and again with small bursts of growth. Raijin winced as one last painful spasm seared though his chest. Squinting, he watched his pecs heave and thicken as another inch burst into them. Several big stretch marks tore across his outer chest pointing toward his delts. A few more tight throbs went though his body as they faded, and he felt that the changes were coming to a finish.
"Whew. That was incredible!" Raijin beamed.
Despite feeling fatiguted as though he had gone through the most intense workout of his life, he felt amazing. He checked himself out in the mirror again. His shredded, tapered abdomen, huge thighs, and powerful upper body made him resemble some sort of giant gymnast, he thought - massive yet somewhat graceful. He considered his new proportions as he did some quick poses in the mirror. What had he gotten on him? Horse... Bull... Tiger... He figured his new physique must be focused on powering his limbs like the strongest parts of those animals. He wondered how much stronger he was now.
He squeezed himself into some shorts that were now skin-tight over his thighs and huge bulge and moved to the spare room where he practiced his karate at home. He quickly went into a stance and practiced a few basic jabs and kicks. After spending several minutes adjusting to his new size, he was quickly impressed with how precise his movements were. He worked his way up to some more acrobatic kicks and even challenged himself to some jump kicks that he sometimes struggled with. His new strength allowed him to power through them with little difficulty.
He took a breather and stood looking over his body once more. That's when he noticed...