The problem is, what you want, can not physically exist.
Now, I know we see it in Hentai all the time.. but that is not a good representation of real life

And Shadowrun, despite its Fantasy elements, still tries to stick to realism. (well, as much as it can)
Think about what you want... you want something that can retract, has strength, is prehensile, and flexible. So
how exactly do you do that!??!?!?
To be flexible, it would need a Mechanical gimble, flyjoint, sprocket or lever... that has mass... and you would need one at
EVERY POINT OF ARTICULATION.
Next, those gimlbes, flyjoints, sprokets, or levers need to receive both power and command signals, which means wires....
And we are not even into little things like weight, ductile strength, tensile strength, thermodynamics, mass, or even Phyics!
****
I am sad to say, But Rule 34
ONLY applies to the internet..