ABANDONED. Aliens can reverse body aging to any development stage

[Astor]

In the early 2000s, I read a book where aliens were a million years advanced ahead of us. They had perfected the science of rewinding their bodies development to whatever stage (teenage, adult, elderly), whatever desired. They also lived on a planet where a few individuals were infected with a virus that allowed them to quickly repair their bodies if they became injured. They didn't like it and only one or two were infected with such regeneration powers. They guarded their secret.

The book cover had some kind of crystal structure, which was supposed to be the accumulated droppings of one of their indigenous lifeforms. They were vegetarian, and didn't kill anything, unless they had to. One of them even had a rat as a pet. But they had very strict capital punishment laws. They were benevolent and helpful. Anyone know the title of this book?

[Lobstergirl, au gratin]

Astor, are you still looking for this or did you find it?

[Kris]

No response, moving to Abandoned folder.

Astor (OP) was last active on the site in June 2018.