As terrifying as the sound approaching him was, Jim knew that he had to get help if he ever wanted to grow back to normal. He clenched his fists and stood his ground. It took all the courage he could muster to not run and hide.
"H-Hello!?" he shouted. "I need help!"
The footsteps stopped outside of his door. "Jim?" a voice said. He recognized who it was.
The door swung open, like a building collapsing sideways, and he winced as it moved in front of him, blowing a breeze his way. Then, he saw the owner of the voice.
"Jim?" his 9-year-old sister, Judy, said, looking around the room above him. Jim froze. She was 5 stories tall and dressed in her soccer uniform. She took a step into the room, setting a gigantic green-socked foot down near to him, shaking his world. He realized that she could crush his whole body under that foot.
"JUDY!" he shouted in panic.
She looked around for the source of his voice. "Where are you?" she asked, taking another step closer.
"DOWN HERE!" He waved his arms over his head.
She looked down at him. "What is that?" she asked, confused. "Some doll?" Then, the confusion on her face was replaced by shock and wonder. "Jim?" she said as she crouched down above him. "Is that you?"
"Y-yes!" he said and tried very hard not to cower before her. He was shaking in fear. Some primal instinct in his mind was demanding he run away now. There was a giant beast above him, and he had to escape, his instinct told him. He stayed put, but his eyes focused on her teeth, as he calculated that his head could easily fit in her mouth.
"Oh my God, you're tiny!" she declared. Her voice was painfully loud. "...and naked."
He winced and covered his ears. "Not so loudly!" he said.
"Oh, sorry," she said more softly, covering her mouth lightly with one giant hand. "What happened to you?"
"I-I bought this balloon," he said, pointing at the balloon between them. "It's magic, and I accidentally shrank myself with it."
Judy knelt in front of him, causing a minor earthquake. She picked up the balloon and lifted it far out of his reach. "This is a magic balloon?" she said turning it over in her hand in front of her face. She did not sound impressed. "It looks like a cheap party balloon."
"It did this to me," Jim said. "Trust me. It's magic."
Judy looked down at him. "Wow," she said, drawing out the word in awe. "That's amazing," she said and looked back at the balloon. "Amazing."
"I need your help," Jim said. "I need you to blow in the balloon. It will grow me back to normal. You just have to blow it up again."
Judy knelt there, looking down on him, and both of them realized at that moment how far the power relationship had shifted between them. She literally held his future in her hand. The power was all hers now. Jim waited nervously for her to respond.
Judy looked at the balloon and back down at him, contemplating what to do next. At last, she came to a decision. She said...