Holding back laughter, Ty could barely contain his delight. "Oh, this is too good! This is so much fun!"
The sight of the naked young girl before Ty started swirling odd thoughts in his head. Before Dustin could launch into abuse, standing there soaking wet and now female, Ty decided to make some more changes.
"Okay!" Ty began. "You're now my step sister Daphne. You always were and 'Dustin' never existed."
Dustin - now Daphne - staggered a bit in the shower and grabbed her forehead. "Uh..." She looked up and let out a frightened gasp. "Jesus, Ty! What are you doing in here, you freak?"
"You could stand to be a little more feminine. And nicer to me." Ty willed.
Dustin complied instantly, mind warping. "Er... sorry, bro. I just... you know I'm sensitive about my body, okay? You know better than anybody how insecure it makes you not developing. The other girls pick on me all the time."
"Hey, sorry sis, I know. I just wanted to brush my teeth." Ty lied, watching as his new sister stepped out of the shower and covered herself with a towel.
Ty walked over to the sink, grabbing his toothbrush and watched as Daphne did the same. "I just wish I'd start growing, you know? The doctor says it's late puberty, or a lack of some growth hormone, or something weird like that." She sighed heavily, and smiled. "But at least I've got my brother, right?"
"Yeah!" Ty smiled. "And... and... you know I love you, right?"
Daphne looked at him and smiled sweetly. "Me too, bro." She sighed again. "I just want to be a normal sixteen year old girl sometimes."
Ty grinned, feeling excitement in his gut. "I guess I'll just have to make you a normal sixteen year old girl, then."
"Whoa!" Daphne suddenly dropped her toothbrush and took a step back from the bathroom counter. "I feel really weird!"
"Huh?" Ty played it off. "What's wrong?"
"I-I'm tingling all over! It... it!" Daphne took another step back and gasped. "Gotta... gotta sit down for a second." Dizzily, she sat down on the toilet bowl, still wrapped in the towel, and began to progress in physical development.
Ty watched with amazement as his short little sister suddenly began to grow and fill out into a young woman. She became much taller, much bustier, and much more curvy. When it was all through, Ty's former step brother was now a rather impressively attractive curly haired blonde bombshell.
Ty blinked. "Uh, Daph? You okay?"
"Yeah... oh, weird." Daphne shook his head as if clearing it. "I think I just got dizzy or something."