short-term thinking
It appears that, sometime in the past, someone either taught Giovanni to be a shoulder-and-neck-sitter or declined to discourage the behavior. That's really cute with a 2-pound kitten. Ahem: they do not stay two-pound kittens forever. This is a terrible picture (Giovanni loves to investigate the camera instead of sitting still if he detects it), but to get an idea of scale:

And here are a couple pictures of Orlando:


Orlando did not go into hiding again after the vet visit, and yesterday afternoon he spent an hour or so in my lap in the living room (yay). Giovanni likes my office, particularly the computer desk, but is reluctant to explore the house much -- coming into the room next door while I was watching TV last night was a big stretch, and he's made some brief late-night forays into the bedroom. So far as I know he has not yet been downstairs under his own power. How do I nudge him along in that? I don't want a litterbox in my office forever.
For all the suitable places in the house, particularly for Orlando, I'm surprised that they both tend to sleep under the same chair in my office, concurrently.

no subject
Which is why I suggest getting Giovanni to start using the one in the basement. Otherwise, you'll have a litterbox in your office for the rest of his life.