As nice as having breasts felt, they were his sister's and David felt a tad guilty with them sat on his chest with his sister being oblivious to the fact that she had in effect been 'robbed'. Sighing quietly to himself, he concentrated hard and then glanced down as his t-shirt began deflating, his sister's breasts melted into his chest and regrew on her chest, filling her bra again. "Why do you keep zoning out on me?" Alicia asked, as she adjusted her bra strap a little.
"Huh? Sorry, just a little distracted." David apologized.
"No shit little bro, but by what? You can tell me, I'm your big sis and maybe I can help you if it's anything that's worrying you." Alicia told him, trying to sound more like a mother than a sister to David.
David chuckled, sitting back with an erection still pressing against his boxer shorts. "There's certainly nothing worrying me sis, far from it." he said, pondering whether to tell his sister about his new power and bring her in on the fun.
"Then what is it? You're definitely acting weird." Alicia narrowed her eyes, trying to force the truth out of her brother.
David just smirked at her, which only increased her curiosity and determination.
"Come on, spill it, whatever it is." Alicia more or less demanded of her brother while folding her arms.
David thought about it for a moment more, then made his decision. "I can swap people around. Their body parts I mean, their traits, whatever you want to call them." he revealed, only to receive a skeptical stare from his sister.
"Yeah, real funny. Now stop messing around and tell me really what's going on." Alicia rolled her eyes.
"It's the truth!" David said firmly, still smiling. "You want a demonstration?"
Alicia sighed, then decided to call her brother's bluff. "Yeah go on then, swap something with me." she stated, gesturing to herself and not believing it was possible. She then sat there as her brother studied her for a moment, then seconds later she felt a faint tingling in her throat.
"How's this for a demonstration?" David suddenly asked, speaking in Alicia's voice.
"Woah... what the fuck?!" Alicia blurted out in her brother's voice, before slapping her hands over her mouth. "I sound like you." she then said, as one hand ran down her neck, feeling her new adam's apple.
"Because I swapped our voices. I was telling the truth sis." David winked, his cock hardening again as he heard his sister's voice leaving his lips. "And just to come clean, a few minutes ago I had your boobs too, but I kept you unaware."
"You what?" Alicia frowned, feeling a little uneasy about all this.
"Relax, you're my sister, so I gave them back." David reassured her, as Alicia reached up to give her boobs a gently squeeze.
"Well, good." Alicia mumbled in her now deeper voice. "Now can you swap us back, I'm not sure I like sounding like a guy, even my own brother." she asked him, and she quickly got her own voice back. With that done, Alicia's sense of 'unease' began to get replaced by one of excitement and wonder. She wanted to see more demonstrations involving her brother's new swapping power. "You want to head out and show me what else you can do?" she suggested with a wry smirk.
"Great idea!" David nodded, grinning all the while. The siblings finished their sodas and then left the dorm.