Derrick stared at Grok as he slowly came to his senses. He cupped his forehead into his hands. This was insane; he was a human, not a hairy neanderthal brute. His new caveman equipment had taken over him. Derrick almost gave into it, too. He shuddered as he thought that he had actually called himself "Drok", and had imagined himself fucking that hairy, stinky beast before him. Still, his caveman cock was still pounding erect, jutting out from his smelly bush, leathery and criss crossed with veins. Other than that, Derrick still looked relatively human. If he left now, he could probably still pass for human.
Derrick found he was staring at Grok's huge package and his hairy body, and he was getting more turned on. "No, I have to fight it!", he said. Grok sauntered over to Derrick; "Just give in, Drok. Fun to fuck with big cock", he grunted. He looked down at his huge hairy cock again, fully hard. "No, I'm not Drok. I'm... I'm...", he muttered to himself unconvincingly. "Derrick!", he said, shocked that it took him so long to think of his name. He had to fight this. What would his family think if he lt himself become a hairy, smelly caveman? Would he ever leave this place?
Derrick found himself staring at Grok's huge cock, his eyes tracing up his hairy torso. He stared at the sweaty curls on the neanderthals chest, and his eyes stopped on the musky bushes that stuck out from the beasts armpits. "I wonder what those smell like", his mind thought to himself. Grok saw that Derrick was losing the battle, slowly becoming Drok. He smiled and stepped forward. He raised a hairy muscled arm, showing off his massive bush. "Smell good. Smell like man", Grok grunted. Derrick's eyes glazed over as a thick, musky BO washed over him. Grok stunk so bad, but it was making Derrick so horny. He was practically drooling. "Yes. Me Like. Smell bad and good", Derrick grunted back.
Grok took Derrick's hand and placed it on his hard furry erection. "Feel Grok's cock. Feel nice", he said. Derrick looked down and saw his hand was gripping the caveman's member. It was so huge! Grok smiled, knowing Derrick was his now; "Taste good too", Grok said. Derrick was in a daze from all the body odor swimming around him and the caveman testosterone buzzing around his system. He slowly lowered himself to his knees. Grok smiled. He grabbed Drok's head and forced the thick cock into his mouth. Drok's eyes bulged out; it was huge! Grok's member tasted rank and sweaty. Derrick's nose was in Grok's sweaty bush, and it smelled terrible. Normally, he should be disgusted, but he found he was quite turned on.
Within a few minutes, Grok grunted. He shot load after load of thick, stinky caveman cum into Drok's mouth. Drok swallowed what he could, but it was too much. Some of it spilled out. Drok felt his face and forehead ache moments later. His brow began growing, jutting out immensely, a huge ridge of bone forming. This gave him a very brutish and simian appearance. Likewise, his nose became huge, wide, and bulbous. His lower jaw grew large as well, jutting out from his face. These made his face look quite devolved and simian. Derrick's old human face was underneath it somewhere, but he needed a few thousand years of evolution to make it come out again. Drok's face itched as thick stubble and hair sprouted, giving him a short beard. Derrick had never shaved before in his life. Drok laughed to himself as he realized he probably would never touch a razor in this new life, either. Thick eyebrows formed on the bony ridge above his eyes. They combined into one thick, hairy uni brow. Drok grunted as his teeth became crooked, cracked and yellow. A huge adams apple pushed its way out of his hairy neck. Drok grunted again, this time much deeper.
Grok smiled as the latest change finished; his caveman cum had done a number on Derrick. Derrick now possessed the head of a caveman and the cock of a caveman. Grok knew there was still much work too be done; his body was much too weak and devoid of muscles. Drok's skin was too pink and soft, and totally devoid of hairs. Drok's spine was much too straight, his arms much too short, and his legs much too long.
Drok felt his knew, deformed and hairy face with his hands a grunted. He had to fight back! He didn't want to end up a nasty caveman! "I. No. Want. Drok.", he grunted to himself, finding that English was vastly becoming too difficult and complex for him. Drok looked in horror as Grok walked over to him with a smile, ready to initiate the next changes...