Watching as the progress bar filled up, Jeff sat back on his chair, his arms and feet dangling off the chair. It appeared to be that nothing was happening, but something like this took time, and few some research in his own time, jeff knew that the Chronivac wasn't an instantaneous device. It had physical limits, especially as it was bending laws of space-time as it caused the changes.
It was perhaps about 2 or 3 minutes after pressing the input button did Jeff feel somewhat weird. The feeling, although faint, was occurring on his hands and bringing them to his face, he took note of how stumpy they were. While still retaining the 5 digits, human hand appearance, they looked smaller then as he remembered. This could mean anything as it could be a race he knew of, or one created by the Chronivac, but Jeff had little time to ponder as his legs also felt weird.
He took a glance down at them and while he couldn't see anything due to his jeans, he could feel changes occur. He wanted to try to feel through the fabric of his Jean's to see if anything was going on down their, but as he tried to lift one leg closer to his head, the other one lifted itself up as well. With a little more experimentation, it seemed that both his legs can only move in unison, no longer as individual limbs. Perhaps due to what race he was becoming.
Jeff's mind was trying to process his changes and transformation, releasing waves of dopamine due to the excitement. Jeff spent the next few minutes just observing his current progress with his hands and arms getting shorter and smaller with the opposite in fact, happening to his legs. They just kept extending further from Jeff's body and also apparently merging. His jeans were tearing at the seams as his legs merged and became more round ish and fatter. They even were beginning to bend in ways normal human legs shouldn't be able to.
With how things were going, Jeff could only come to the conclusion that he was becoming a lamia. Although saddened that he would no longer be able to have hands anymore, the long tail and poison abilities would make up for it.
With his arms now just a few inches long and his hand just small stumps, Jeff kept a good eye on his 'tail' as it extended outwards. Its huge bulk was actually filling almost all of the space in his room, and with it still extending, Jeff estimated it might even reach 50 to 60 feet in length which is somewhat shocking to say the least. The tail also began to form scales in the style of an anaconda, the dirt brown and black scales forming on the mass of flesh.
Even his own face wasn't saved from the changes, although Jeff only really noticed out his teeth had began to form fangs with a venom (that was harmless to him) could kill a creature of his size. He even felt his muscles and skull alter so his mouth could extend and engulf very large creatures and races. Perhaps he could even swallow a centaur whole and listen to it scream as it is being eaten alive (although that thought was somewhat scary as it meant he wasn't bothered to kill a sentient being, and found him thinking like a sadist).
With him being somewhat shaken by his disturbing thought process, he couldn't take notice as his vision began to see a different spectrum of colour as his vision could see infrared radiation and heat detection but not much else, with his brown eyes becoming yellow and reptilian. His tongue wasn't saved from the changes either as it became forked, but he could also find that it could pick up a larger sense of smells and tastes to track down prey.
His clothes also were changed by the Chronivac. His ripped jeans became more like rags and formed a weird skirt like thing around his waist. As for his shirt, simply vanished and around his somewhat more muscular chest were strange tattoos which, with some new memories from the Chronivac about the new world, Jeff knew represented as being part of a swamp-dwelling lamia tribe which were known to be incredibly huge lamia.
Also, as part of being a lamia, even his groin was not safe from the changes. As the scales ended just above his waist, he penis ended up having a push form for it. This pouch had scales to protect it and certain pelvic muscle could be used to retract the scales and release the more fleshy, and large penis that Jeff was now endowed with, although his testicle were more internal due to the pouch and no need for them to be external.
One last change that wasn't clearly visible or noticeable was Jeff was now cold-blooded, meaning he will instinctively relax in a hot sun to warm himself up and go dormant uf it's too cold. Jeff wouldn't know these actions weren't normal for him when he was human due to it being subconsciously being done.
Jeff's body was completely finished to his changes. A tattooed upper body without arms and a snake tongue and snake eyes; with a 60 foot anaconda snake-tail replacing his legs and incredibly powerful muscles. Jeff felt exhilarated at his body, although he couldn't completely look at it well due to his now changed vision of heat/infrared.
Jeff wasn't expecting much else but when a wave of nausea hit and he found himself dwelling in a warm, sun-filled swamp with a hot, humid sun warming his body. He was perhaps somewhere around the equator but it was hard to tell with his different vision. What jeff could tell though was that he was with some other lamia like him, and one of them, a female lamia, was someone if importance to Jeff. His mate.