"hey ken" Eric said, trying to get his brothers attention. Ken looked up. As his stared at his brother he furrowed his more prominant brow. "what...you want" he said. "I was wondering if you were feeling allright?" replyed Eric. "me...ok, tired, me sleep now". With that Ken got up and made his way to his room. His slumped posture, and even more muscled body than before was clearly evident as he passed. Eric wondered what was going to happen to him .
That night as Eric tried sleep he thought to him self, why did he look up the caveman templet, and what was it about his borther. As he did this his cock stired in his boxers. He realized that there was something so alluring and hot about the primal muscle and hair his brother was developing. He wanted it bad. The idea of giving in to ones simian urges and losing all control...
The next morning Eric woke up to find that Ken was gone. Ken had subconciously gotten up at dawn. He was able to remember to put on clothes and had gone to the gym. But his car was still in the driveway? he must have walked Eric thought. Ken couldnt rememeber how to drive, and it wasnt that far.
At the gym Ken worked out like crazy. It was his strongest urge now, second only to eating, and sex. After about two hours he left and made his way home. ON his way he noticed that a layer of brown hair had covered his arms and chest and part of his hunched back. HIs spine had also grown and curved to support his muscled torso. His huge pecs were covered in viens and his stomach was an extremely muscled roid gut.His legs increased slightly as well, but his pelvis had widened and his legs splayed out to the sides.
He passed a woman jogging and felt the sudden urge to fuck her. HE needed release. but she gasped and imediately fled his sight. He didnt chase after her. He needed to release the primal beast within him, and he didnt care who it was.
Eric was eating breakfast when Ken appeared. He couldnt beleive the sight of his allmost completely unevolved borther. His extreemly muscled body heaved at each breath. His arms were longer and they stuck out from his frame. Sweat and testosterone filled the air.
Eric didnt know what to do. He was filled with fear and excitment at hte same time. His cock tented in his boxers. "Ken...is that you" ? he said . A grunt and a me was the reply from Ken. Ken didnt need nor want words now. He didnt need them to fullfill his most primal urges.
Ken began to walk towards his brother. as his did he tore off the rest of his clothes, a pair of sweat pants. Revealing his aching caveman cock and balls.
Eric knew what was going to happen, so before it began he ran back to his room and puled up the program on his computer screen. He took of his clothes, and on the screen clicked the final caveman stage box and speed it up.
He quickly ran back to where his devolved brother was and met him face to face. Eric stared at the caveman muscle beast and began to jerk his cock as the final stage of the transformation began. Ken grunting in not pain, but pleasure as his jaw extended further his brow beetled out, and his last thoughts of humanity slipped away..................