As her PJ bottoms fall to the floor Jeff looks up and his jaw drops as he witnesses for the first time in his life his little sister's package which while not particularly big still dwarfs his own Previous size. As she peels off her old dirty panties the reality of his situation dons on him, he is going to have to contain that. "Whats wrong Undy you act like you've never seen a dick before" Sarah taunts Jeff. "SS-Stop calling me Undy, m-my name is Jeff" he protests while avoiding the topic of Sarah's Cock. Sarah plucks Jeff off the desk and begins playing with his body. "Oh Undy you're my underwear now, not a person that old name doesn't fit you anymore, Undy works much better" Jeff tries to struggle out of his tormentors hands but soon finds himself going limp as Sarah reconfigured him to his proper form as her undies. After a short while she seemed satisfied with her work, And Jeff got a glimpse of himself in the mirror where it looked like Sarah was holding an ordinary pair of panties save for his face in the rear.
Fear struck Jeff as he realized what came next "S-Sarah p-please turn me back I don't want to be your p-panties." he whimpered. Sarah just laughed and lowered Jeff to her feet. "Don't worry Undy you'll learn to love my dick and butt eventually." she cooed. As Sarah stepped into his leg holes Jeff began to panic "Please, Sarah don- ". Sarah swiftly pulled Jeff up her legs and snugly into her ass silencing his pleas without a second thought. "Wow you might be the softest panties I've ever worn Undy." Sarah remarked with a pat on her Jeff clad ass "Way better as underwear than you ever were as a person at least." She laughed. "You're right," Chimed in Sydney as she put on her own pair. "Shes the comfiest thing I've ever worn."
As his sisters giggled together comparing their new undies Jeff was just getting adjusted to his new life. His sight was firmly wrapped around Sarah's butt, so all he could see was her cheeks and crack. In the front of his rearranged body he was clinging tightly to Sarah's package which to Jeff's surprise was completely contained by his cotton form despite its size. The worst part of his ordeal was that he could taste and smell everything on the inner part of his body from her cock and balls, to her cute vagina, and finally up to her little brown asshole right in the middle of his face. Luckily for Jeff Sarah had showered the night before so all he could really taste was a faint layer of sweat and fruity soap, but he knew that would only last so long with how Sarah was. While Jeff was still trying to get adjusted to his new position the light filtering in through his cotton body suddenly went dark as Sarah pulled up a pair of jeans up over him sealing him in. He could still make out what Sarah was saying clearly but anyone else who wasn't right up next to them was much more muffled.
After a few minutes of idle chatter between the twins Jeff felt Sarah walk out of the room which was a weird experience as each step pulled his face into her crack, apparently he wasn't the no-ride-up kind of panties. Jeff suddenly feels Sarah start to run and Yell out "Mom I can't believe the panties you got me". He feels Sarah's entire body shift in what can only be an embrace from their mother. "I take it you found your brother then? how is he is he comfy?" He hears his mother ask. "Yeah hes the softest ever!" Sarah replies. "I always knew it! that boy was just about made to be panties. I'm so glad i put that request into Hanes." Jeff's heart sinks as he hears this, in this reality the chronivac had created, his own mother had decided he was better off as underwear. "Mom why'd you give Jeff to Sarah I want to wear him too." Sydney must have walked in the room and immediately started to complain about Jeff's ownership. "Well Sydney, you only have one brother and considering all the physical activity she gets up to and her unique body I felt like your sister needed the stronger pair of the two. but I'm sure the girl you got makes for splendid underwear herself doesn't she?". After a short pause Jeff hears Sydney sigh "Yeah she does and I guess your right." Mom then reassured Sydney "Don't worry I'm sure if you ask her nicely Sarah will lend him to you some time. Isn't that right Sarah?" She asked. "Yeah sure, but only if she promises not to wet him" Sarah taunts. "No fair Sarah you know I can't control that." Interjecting before a real argument comes up their mother says "It's okay Sydney she was only joking you'll get your turn with him eventually."
Jeff was starting to get annoyed at his family for so casually talking about what was going to happen to him as if he was just an object who couldn't hear all of it. Unfortunately for him though there wasn't anything he could do about it as anything he says in protest would only be silenced by Sarah's butt and jeans. Jeff's mother then announces "Now girls, that's enough chit-chat its time to get ready for ___________. "