Drok was momentarily frozen in fear over the changes he was going through as Grok advanced on him. Drok looked at Grok's hands, and saw what seemed to be a large piece of meat. No, not that kind of meat, but a practically-raw slab of steak.
Drok's mouth salivated... but then he realised that everything Grok had given him so far had changed him. And what else would eating a big slab of protein do but grow his muscles. For a moment, Drok saw himself with caveman muscles, and was tempted. But he also realised that it would be the point of no return - if he ate the steak, he would be more caveman than human, and would certainly give in to the rest of the transformation.
With a surge of willpower, Drok... no, Derrick... overcame his hunger, his horniness, and the heady scent of BO of the room, and turned for the cave entrance/door. Grok reached for him, but he still had his human body, so he was nimble enough to slip past Grok and out of the cave...
Wearing nothing but a loincloth, with an erection that was big enough that the loincloth hid nothing. Derrick ran, his engorged dick bobbing and sweat gathering on his huge brow, and every few strides he grunted like an animal at the exertion.
When he reached the elevator, it was luckily open and ready to take passengers. He dashed in and pressed the big "G". The elevator door closed just as Grok approached, and Drok heaved a sigh of relief. Wait... no, Derrick, not Drok. Derrick was fighting to keep hold of his identity, even as his raging hard-on continued to harden further. He feared that giving in to the horniness would lead to his undoing - that it would be another way to fall into cavemanhood.
As the elevator doors opened to the foyer area with the front desk, Derrick hurriedly walked forward. He glanced back to see the elevator heading back to the floor he had left - probably to pick up Grok. He quickly approached the lady at the front desk again.
"Oh, back again, I see," the lady mused, her nose wrinkling up at the smell from Drok's crotch and loincloth. Drok... Derrick... Drok... Derrick looked down at his chest to see more hairs appearing - the loincloth was probably still affecting him. But could he bring himself to take it off, even if it wasn't doing much to cover him? Or would taking it off actually make matters worse?
"Me want other room!" Drok banged his hands on the counter for emphasis, before Derrick realised how uncivilised he was being and took a deep breath. "Quick." He would have made it more polite, but he couldn't find the right word.
"Well, you are quite difficult to please, aren't you?" Drok banged his hands on the counter again, trying to hurry her up but now even having trouble with remembering the word he just used moments ago. "Alright, alright. You still want to be manly, right?" Derrick nodded. "Well, the only other room I can see that might suit is ..."