Jeff was enjoying her body, rubbing her 8 nipples was especially exciting since she now felt pleqsure from areas she never would have ever felt pleqsure from, back before she became a cat girl. With everything so far, while there was the minor unintended swap, she was ultimately satisfied with their results. That being said, her enthusiasm about her new body couldn't maintain its strength when she looked into the mirror. She looked too disproportionately sized in many areas, and her male face didn't work with well when paired with her feminine chest and head. Her limbs could use a few more feminine touches too, especially her arms, which had gone untouched this entire time.
So after opening up a few images of girls he found on the internet, Jeff began the slow and methodical process of stealing a bit from each of them, resulting in her having a now completely female body from head to toe, but none of the girls had lost anything too significant in the process. She had even made her voice fully feminine, however on a whim, she also swapped about 20% of it with Nea's. This resulted in her occasionally meowing instead of using words, especially if a word was similar in sound. She toned it down to only 5% once she realized that she couldn't even go a full sentance without meowing several times. Now she only did it rarely, when startled, or intentionally. However the desired effect, which was acquiring its realistic sound, had been achieved.
With an overjoyed expression on her face, Jeff saved her profile and closed down the program. And so as to prevent anyone else besides her from messing with it, she also fully uninstalled it. But what she didn't realize, was that since she was under a timed transformation, the program had to be kept installed, or the timer would not go down, and simple be paused until the program was reinstalled again. The last thing Jeff did was close out of all of the images, and wipe the history clean.
"There meow no one should ever know!" Said Jeff to herself. She took the program installer with her and left the room. Even though it was her own PC, she didn't trust that her sister simply just leaves it alone whenever Jeff isn't home. At least according to her search history, somehow, she had apparently looked up a variety of toys, online kids games and videos from channels she didn't normally visit.
Suddenly, Jeff had an idea. She grabbed her phone and plugged it into her PC, along with the USB installer. She tried installing it onto her phone as an app, and it actually worked, much to her delight. "Purrrr-fect" Jeff purred intentionally.
She tested the app and sure enough, the same window loaded up, with her profile already pre-selected too. As a test, she changed her name from Jeffrey (Jeff) to Jessica (Jess), saved and closed the app to test if it worked. As if on queue, her sister called for her. "Jessica, do you know where Mom is?"
That was all the proof she needed. Jessica replied "She is not home right meow." Suddenly she heard her sister running up the stairs. A few seconds later she opened the door to Jessica's bedroom. "Wahh, who are you?" She shouted with a scared look upon seeing her new sister. "Where is my brother Jessica?"
Confused, Jessica looked at the app, and noticed an asterisk next to the name box. Pressing it, a text window opened saying "reguardless of other settings, any change to name will always apply globally as if reality changed to where the target has always been called as such, only the user will know the difference."
"Whoops" said Jessica to herself, completely ignoring her sister.
"Whoops what? Where is my brother!" Demanded her little sister again, this time even louder.
Jessica had to put her hands over her ears. "Can you calm it down a bit Hannah? I am still your older brother, well meow I'm more like your big sister I guess. Anyways it is still me so please just stop with all the shouting, meow. It is really starting to hurt my ears."
Hannah squinted and stared down the strange cat lady infront of her claiming to be Jessica. "Are you really Jessica?"
"Yep, I just meow look like this. But that also means that I'm meow your big sister too." Assured Jessica, again.
"Fine then" said Hannah. "Where did Mom go?"
"She went out to get food for the week at the grocery store. She'll be back in like an hour or so from now. Why, what do you need from her?"
"I am going to tell on you, and how you became a cat lady."
Jessica had noticed it from the start, but Hannah had never stopped looking at her cat parts. She loved cats, so maybe she liked them on her too? "Do you want to pet me?" she asked.
Hannah nodded excitedly, having no longer any care about whether this girl was really her brother or not, and walked over to pet Jess. The moment she began, Jess felt such an incredibly strong urge to rub up against Hannah that she slid off of her chair down on all fours and began purring like mad. She just couldn't help it, and softly pushed her head into her sister's body. And especially when Hannah began scratching the small of her back just above the base of her tail, did her purring reach its maximum.