The editor and I did discuss a sequel and I started collecting material for it, but I had changed careers by that point and no longer had the time or motivation to see it through to completion. And now I’m not sure if there’s a market for such books anymore. At least, if I were learning to read Japanese myself now, rather than buying a book of annotated readings I would choose my own texts and ask ChatGPT, Claude, or Gemini about the parts I don’t understand.