Downsized

"I wish I was smaller! Much, much smaller!" Sarah shouted angrily, almost yelling at her breasts.
John had his eyes covered. He was afraid it wouldn't work and she'd decide to go about punishing him. The rock glowed and Sarah's body began to tingle all over.
Peeking out from a crack in his fingers, John looked up at Sarah, eye level with her crotch and past her huge breasts to see her face, startled from the tingling she was feeling.
Slowly, her entire body began to diminish. Her panties remained tight on her skin, shrinking with her as, before John's eyes, Sarah shrank.
"John! What's happening?!" she screamed, her voice getting higher and higher as went under four feet.
John sat up, his eyes now level with her proportionately huge breasts for a moment before her terified face went down past his.
"Do something! Help me!" she shrieked, now in very high squeals.
She went down, past two feet, feeling her body in shock as it shrank and looking around the room rapidly for something to stop her miniaturization.
John actually felt sorry for her, seeing how scared she was and always reached out to touch her as she seemed to stop shrinking at the size of a Barbie Doll, her frantic shouts inaudible squeaking due to her terror and how small she was.
As the tiny woman screamed in front of him, John shook his head, coming out of his shock at how the wish turned out, and smiled. He was safe.
"I guess you got what you wished for," John said to the nearly naked beauty. He turned to pick up the rock, but didn't see it. He looked down, scared again, and saw that she still had it. It had shrunk right along with her...