Cray realized what was happening. Seeing the Hulk on TV had made Guy think of muscles - of muscles growing. And when that happened, his body reacted immediately.
Cray watched helplessly as Guy struggled to control his desire for bigger muscles, but judging from what he saw, Guy was losing the fight. Guy's pecs pushed outward and against each other, his forearms thickened, and his quads were visibly swelling under the blanket that he had tied around his waist.
Cray was shocked, but he also began to be aroused by the growing behemoth before him - by the growing shoulders, by the ever increasing size of his friend's biceps, and by his ever widening shoulders. Only half aware of what he was doing, Cray reached out and brushed his fingers against Guy's incredibly defined eight-pack, feeling the muscles grow beneath the warm, delicate skin.
"Cray!"
"Oh, I'm sorry... your body is just so- I didn't want to-"
"Shut up, Cray; I'm not upset because you touched me. It's because you are growing too!"
Cray looked down at himself and saw immediately that Guy was right. Cray's own pecs, too, were pushing outward; his biceps, too, were inflating with size. Cray told himself that he needed to stop this, that he had to concentrate and imagine himself as smaller - but seeing Guy's muscle growing right in front of him made it almost impossible for him to focus, and so his muscles also kept increasing in size.