"I want to change you so you can see how it feels!" Dawn would let out, glancing over at the computer that her brother had been typing at just before she'd entered the room.
An apprehensive look would find its way onto Luca's face, but Dawn wasn't one to gave Luca much time to think it over. Though she was a 16 year old girl, she and Luca were pretty close in both height and build, so it wasn't a stretch for her for consider making a move on the computer.
"Hey, just wait a second, alright?" Luca would say, placing his hands out as if to hold off his sister. He'd place his smartphone beside his computer, before glancing over at her.
"I changed you using some software called the Chronivac, okay? W-We both know you get self conscious over the fact that you're..." Luca cut himself off as he noticed the annoyed look on Dawn's face.
"Don't you dare say it...!" She would practically hiss, causing Luca to nod quickly.
"Alright, but am I wrong?" He'd let out, causing his sister to let out a sigh. She'd stop her attempts at trying to hold up her training bra, letting it fall down through her shirt and onto the floor.
"No, but... Geez, you could at least ask me before you go ahead and change my body like that!" Dawn would let out before pouting, crossing her arms underneath her new chest.
"S-Sorry..." Luca would let out, thinking for a bit before stepping away from the Chronivac. "But I guess you're right, it's only fair you get a turn to use it on me. Just... don't go too overboard?"
"No promises~!" Dawn would say, her pout disappearing almost immediately as she'd quickly make her way over to the Chronivac. Looking it over, she'd type something in, before tapping the enter button.
Luca would brace himself for whatever she'd put in, but was surprised to see that Dawn was the one changing again. He tried not to look as her chest seemed to go up yet another size, resting at C-Cups. "You... made them bigger?"
"W-Well, this size just suits me better, wouldn't you say?" Dawn would say with a slight blush before she'd pick up Luca's smartphone that he'd left behind on near the Chronivac. "Anyway, I can use that thing on your phone too, right?"
"I mean, I'd rather keep my phone to myself if you don't mind..." Luca would say, only for Dawn to shake her head.
"But that's your phone, the computer, and the remote. You get 3 ways to use this thing and I get none?" Dawn would say, soliciting a sigh from Luca. Wasn't the package addressed to him in the first place?
"Since you seem to really wanna keep the Chronivac that badly..." Luca would say, taking back his smartphone and removing the chip he'd installed. "Take this chip and put it in your phone. I'll keep the remote, and we'll both try to stick to using it that way."
"What about the computer, though?" Dawn would say, grinning as she'd install the chip, and therefore the Chronivac app, onto her phone. "Are you keeping that too?"
"We'll both try not to use it, to keep this little arrangement fair." Luca would reply. "It can override any changes the remote or app make after all."
"Sounds good to me!" A thoughtful look would settle on Dawn's face, though. "Um... before I go ahead and test it out on you, any rules or things I shouldn't do?"
Luca would pause, taking some time to think to himself as well. "Well, in general, I think it'd be good to keep both of us aware of any changes made. So, no reality changes that would make either of us unaware of what the other might do. Other than that? I guess we'll just make it up as we go?"
"Alrighty then, so..." Dawn would trail off, glancing down at her phone now.