When Adam wakes up again...

When Adam woke up again several hours later, it was to the sound of his sister's loud moaning. He wasn't sure that he was fully awake yet, but his cock surely was, and it was rock hard. He could feel with every movement the friction of Sarah's tight pussy and sighed in pleasure.

When he opened his eyes, he realized that he no longer lay on top of her. Instead his sister had managed to reverse their positions, and while his back was now on the mattress, Sarah was on top of him, grinding her pelvis into his, riding him cowgirl style. He looked further up and was easily hypnotized by the jiggling of her breasts, but something seemed off: They appeared to be quite a bit bigger than he remembered, rounder, more jiggly. His first thought was that he must be imagining things, but when he thought about his own "Growth X" powered cock, nothing seemed impossible.

He looked up at Sarah's face, and Sarah's eyes looked back at him. He could see that she had an expression combining devotion, pleasure and happiness.

"Aaah, you are finaahah.. finally awake."

"Sarah. What's up with your tits?"

"Yes! Aaah. They have grown, haven't they? Hmmmm. How is that even possible?"

Adam tried to make sense of it, but he had a hard time to focus on logical reasoning, while his sexy and now very busty sister was riding his huge and hard cock. Of course it had to have something to do with the "Growth X" pills, that much was obvious, but until they finished with fucking, the specific cause had to remain a mystery.

"I don't know, but i like it. Perhaps they will grow even more? It is only appropriate that my first slut has huge tits to go along with my huge cock. Would you like that my slut?"

"Aaaah, Yes! And they are really sensitive now. Won't you touch them?"

"Sure. My pleasure!"