Jon had been a vagina for he guessed two hours now. He was already well aware that being a vagina sucked. He had no idea what Sarah was up to and with her clothes on he couldn't see anything.
He hadn't heard Sarah say anything for a while and the only sounds he had heard lately were car noises. She must be driving somewhere, which was silly because she had the stone.
Every once in a while he felt Karyn move next to him. It was beyond frustrating to be literally less than an inch away from your best friend but have no way to see or talk with her. In his boredom, Jon had used the time to attempt to study himself. He had previously had no idea if he was literally just a vagina, or if he had more "parts" to his new body. It turns out Jon and Karyn were each full and complete female reproductive systems. The stone must have loosely interpreted Sarah's wording OR Sarah mentally was thinking about her 'female bits' in general as she spoke the wish.
When he first became a pussy, Jon had likened moving his labia to moving his mouth, the truth was far more complicated. His mind now controlled and received input from a completely different structure than it had been in previously. Learning to "move" and "feel" in his new very limited capacity was akin to someone in trauma re-learning to walk again. In addition to moving his vaginal walls he could contract his cervix a bit, as well as a few other muscles. Of course, twitching about in Sarah's groin wasn't really going to get him anywhere. Also, as he was jostled about in Sarah's body he could feel his fallopian tubes and ovaries stretching upward into her pelvis, but had no way to move them.
So, Sarah had four ovaries, two uteruses, and to vaginas. The thought occurred to Jon that Sarah could have sex and impregnate both him AND Karyn anytime she wanted! There was nothing either of them could do about it of course, they were simply her sex organs now. Jon was frightened at the possibility of going through a pregnancy within what was essentially his WHOLE body!
Jon was snapped back to reality as he heard the car shut off. Sarah must have arrived somewhere.
"Hey guys." Sarah suddenly said aloud. "Don't mean to interrupt you down there but it's time to go to work. I gotta pee!"
"Oh fuck" John thought.