Portb
Just then Katie's cellphone went off -- with the ringtone from "Stronger"

"Yeah? Oh yeah!"

"I told you he had a thing for me".

"He would if I told him to. But that's not the only thing."

"Uh uh. You'll have to see. Well yeah! No! Perfect!"

She hung up and grinned at Arnold. "Angela and Evie are coming!"

"But you were going to let me ...."

"Change of plans."

The doorbell rang. "Come on! That's them." Katie pulled him, nearly tearing his arm off. "They were waiting across the street in the park." He tumbled after her, crashing into her broadened, muscular back twice as they went down the stairs but not knocking her off balance. Katie stopped short. "Will you get a grip!"

She bounded down the last five steps and pulled open the door. Her two friends were waiting. Angela was tall and thin and always seemed a couple of seconds behind everyone else. But she was a loyal friend, with a keen sense for fashion and clothing, and matchless in cooking, drawing and sewing. Evie was short, with a large bust and hips. She was emotional, enthusiastic and had boundless energy and a limitless appetite for pleasure.

"Katie?!" Evie screamed. "You’re so buff! What happened to you?"

"I'm Mega-Katie," she screamed back, pulling Evie inside. She grabbed Angela too and shut the door.

"I didn't know your real name was Meg!" Angela said, confused. "All these years and you never told me.. Hey! You know your top doesn’t fit. What's with the muscles? "

"Not Meg, Ange. Mega! Like super!" Katie said, exasperated.

“Oh! Yeah! I get it!” Angela said. She looked at her and shook her head. “I didn’t think girls got muscles like that from working out.”

“They don’t.” She pointed at Arnold. “They get ‘em from him. Come upstairs. I’ll show you.”

“But that wasn’t the deal!” Arnold protested.

“Hey, you like muscles on girls. Now you can make three girls mega-powerful!”

“But they ... I didn’t want anyone to ... you know,” he stammered.

“So, you’re not going to do it?” Katie said, looming over him. She picked him up and slammed him against the wall.

“Owwww!” Arnold said. “Why do you keep hurting me?”

“’Cause you’re not doing what I tell you.”

“I don’t have to ...”

“No?” Katie said, still holding him against the wall with one hand and flexing her enormous biceps with the other. “Oooooh, I think you should have thought about that before you made me so strong! Now, are you going to help, or do you want me to use it on you and make you even more of a weakling than you already are?”

“Um ... ok. But will you let me ....”

“Shut UP and just do what I say, if you know what’s good for you. Come on, ladies!”

They followed Katie up to Arnold’s room and Katie positioned them in front of Arnold’s book case. She checked the setting on the gun and then handed it to Arnold. “OK. Now shoot it so you get all of us. I want you to make Evie and Angela as strong as I am now, and make me even stronger. Got it? And if I even see you touch the other controls, I will shrink you down to ten inches and then see what you’re good for. Do you understand?”

Evie laughed. “Ten inches?” She shifted the weight on her hips. “Mmmmmm.”

Katie handed him the gun. “OK. Once I’m back there, shoot all of us.”

Arnold looked as unhappy as could be. This was turning into a nightmare. But he had no choice. His hands were trembling. He fired, but the beam jiggled all over, sometimes hitting the girls and sometimes the book case.

“Can’t you aim better? Jeez!” Katie said. They all started gaining muscle, but slowly as the beam kept missing. “Just keep going. We’ll take as much time as we need.”

“Ooooh, look at me!” Evie said, striking a pose and watching her muscles grow. “I’ve got biceps bigger than my brothers! And my fat’s disappearing.”

Angela was frowning slightly. “Now nothing fits!” she complained, mildly. “But, I guess I can alter my clothes. It’s kind of nice.”

“Yeah, I’ll say!” Katie said. “I’m WAY beyond any male bodybuilder now! I bet I’m the strongest person in the world! What do you say, Arnold?”

He nodded. “C-can I stop now?” he pleaded. “My finger’s getting tired.”

“Yeah, you can stop. For now! Hey girls, I think it’s time to go out on the town and see what these bods can do!”

“Yeah!” Evie said.

“Well, if you think we’re not too indecent,” Angela said, hesitating.

They went downstairs laughing.

Arnold let the gun slip to the floor and slumped onto his bed.