Since Unreconciled Stars established important world-building information about constellations, fate, and the possibility of the sky being fake, it's very likely they'll follow up on this plot thread in the future. This is all directly related to astrology and therefore Mona, so it's a given she will be involved and even the main NPC.

Scaramouche is the only character (that we know of at present, other than perhaps Mona's master and Pierro) that knows something more about the false sky -- it's likely that he will be involved as well. Whether as antagonist or teaming up with the Traveler and Mona remains to be seen!

Of course, as like to believe that there will be a Part 2 with a Scaramona reunion ^^ We'll just have to wait and see what fate has in store ~