The author is working in Kronotsky Nature Reserve ([link]) as an inspector. So all those animals are real, kinda part of his work. I guess he is not keeping them in an ordinary apartment in a big city.
-This fox is in Russia, where they are domesticated -Their gallery is full of foxes on leashes, lying on beds, ect... -Even places where foxes are not domesticated, it's possible to own them as a pet if you get a wild animal license.
There is a small strain of 100 foxes in Russia that are "domesticated", but that doesn't mean all foxes in Russia are domesticated. They technically aren't even real red foxes anymore, due to body changes.
There was an article in National Geographic about a group of scientists somewhere in northern Europe where they were trying to find the origins of domestication. They managed to domesticate the native fox and they turned out to be more intelligent and affectionate than dogs. XD
try to google it - sometimes they run out of money or have other problems and thus they are forced to kill them and since all the scientists have grown attached to their foxes they prefer to find a "foster family" instead of killing them^^
They bite as much as cats or dogs, but they do it playfully. High energy means that they run around constantly and will destroy your house and everything you have in it. Check out foxalbiazul's videos on youtube to see what having a pet fox is like. (Videos can't come close though)