For years you had an idea. Make your self a Humantaur. Now with the power of the Chronivac, that idea was possible.
You opened your profile and began editing your skeleton you doubled your spines length then curved it 90 degrees behind you. You added another rib cage below the waist, connecting legs to were the arms would be. You made it so you had another human torso attached to your waist, with the arms being replaced with legs. You also increased your muscle mass to that of a body builder, and deleted your need for clothes. Once satisfied you hit enter and wait for the changes to start.
Immediately your clothes vanished and you were left naked in your room. You stood up and watched as your height increases along with your muscle. You were given an athletic body that took years to build up and started flexing. Watching your new muscles ripple as they grew. It was everything you dreamed it would be, and it was only just beginning.
Just then you felt a pressure in your waist and leaned forward, catching your self on your muscular hands. Your pelvis shattered and reformed into shoulder bones as a second pair of muscular shoulders, just as strong as the ones on top grew, your entire bone and organ structure changed as your stomach, lungs, and liver all grew down into extra pairs. Your d*ck was swallowed up in musculature as your abs extended down your new torso. Your nerves weaved webs through your new pink flesh and you started to moan as your second set of legs and a new, stronger larger c*ck grew from your second waist. It was almost the size of a horses, and was beating against your lower abs like a drum. You felt your second heart beating blood to your lower organs and let out a gruff sigh as you felt more energized than you ever had in your life. Having two hearts was doing wonders for you.
Soon the changes were done.
You stood on four human legs for the first time and sighed, flexing all your limbs hearing your bones pop.
You did some walking, getting use to having four legs and the feeling of your erected member never going away. Why would it? You dreamed of this day for years.
You looked in the mirror and saw a perfectly crafted human male with another torso coming out of his ass. You reared up on your back legs and saw your 16 pack in all its glory as it trailed down your body to your lower waist. Your front feet slammed down causing your house to shake.
You grin ear to ear.
This was the form you wanted all your life...