Karyn said, "Oh my god, Jon!"
"Karyn, you have to help me. Please!"
She didn't want to, but she also didn't want her best friend to be a freak. So she allowed Jon to ram his dick up her ass, and after he had cummed, his penis returned to its normal size.
He breathed heavily as he sat back. "I'm so sorry, Karyn. But I had to do something about it."
Jon expected her to say something about it, but Karyn really didn't want to talk. She just wanted to forget what she had just done.