Jeff thought a little about what it would be that we wanted to do and eventually decided to come up with something for his sister, Caitlyn. Admittedly, Jeff did feel some sexual attraction towards his 18 year old sister, considering she was a buxom brunette with an attitude. This attitude though did annoy Jeff as some teasing and embarrassing bullying pissed him off, enough so that he wouldn't feel sorry for what he would put her through. Jeff began to type away at his plan.
Phase one: the physical changes
The first changes put into the Chronivac won't be mental changes just yet. They will last for about 3 hours and will permanently affect her if she ever wears clothes that try to cover her up. At first, her breasts will begin to lactate and grow to the point her shirt will get ruined. Thus will cause Caitlyn to change her top which will get ripped apart by her expanding breasts. She will notice the changes, but will be unable to tell anyone about them and anyone besides Jeff and her will think it's normal. While this is happening, Caitlyn's ass and thighs are also expanding and ripping her panties and jeans. By this point, all of her clothes will be too small to fit her and she will have to walk around naked while dripping milk everywhere. If she tries to wear any clothes that can fit her, her ass, thighs or breasts will expand so the clothes rip and force her to stay naked.
Phase two: the mental conditioning
After three hours, Caitlyn's breasts will suddenly start producing milk at a much faster rate and her breasts will feel increasingly heavy over the next hour. As another side effect, her nipples will enlarge and lengthen to a similar size and shape to a cow's teats. Caitlyn at this point will have thoughts about being a human cow that will linger at the back of her mind but she will try to deny it. Eventually, due to the weight of her breasts, she will be forced to crawl on her hands and knees which will relieve the strain on her back but make her start to slowly accept the fact that maybe she us a cow. Even at this point though, Caitlyn will try to think if things a cow can't do that she can such as math and operating electronics, but when she tries to do them to prove her mind wrong, she will be unable to do them as her memory will go blank. This is the point when she will be unable to communicate in anything but moos. The final part of phase two is that Caitlyn will have an urge to both defecate and urinate. When she tries to use the toilet though, she will be unable to use it due to losing the comprehension to do so and the feeling will get so bad that as she tries to go to her parents about it, she will poo and piss on the carpet in the living room, as she cries from embarrassment.
Phase three: the acceptance
The final phase is one that Jeff will help to finish. Feeling despair from her situation, Jeff will comfort Caitlyn in her situation with words and actions. The first thing Jeff will do is place a Cowbell around Caitlyn's neck with the initials C.C. engraved on it. This will both confuse and upset Caitlyn who will try to moo in protest but will be unable to stop it. Jeff will speak comforting words to Caitlyn, but specifically not treating her like a human. Jeff will only call her a cow or her name CC, whilst saying things that relax Caitlyn and make her slowly accept her situation. Jeff will also begin to milk her, grabbing her teats and collecting the milk in water jugs. Whilst this will upset Caitlyn and make her protest, the words Jeff says will calm Caitlyn down enough to where she will accept being milked as normal. As a part of congratulating CC, Jeff will slap her large ass where the ripple causes Caitlyn to defecate again. Jeff, seeing this again, will treat it as ok for it yo happen and that cows do it normally, calming Caitlyn down enough to accept her change and embody her existence as a cow. With a stroke on her head from Jeff, she moos as a complacent and ignorant cow would.
And now with the sequence programmed into the Chronivac, now it it was just a waiting game. So Jeff got a snack from the kitchen to watch it happen.