This one is ruined by all the filler. Author made several one dimensional morally black enemies that exist only to make Calliope look good with the moral high ground while denouncing their crimes but meanwhile the real plot has stalled for a while. We've barely seen who the actual antagonists are and their motivations and there's just too many characters being introduced that you can't be bothered to remember because they don't seem to be plot relevant at all. The scenes with her family are kinda ruined because they are mostly one dimensional characters who pamper her endlessly, and with Calliope being an adult and acting too much like one while inside a child's body the interactions end up feeling creepy or flat. A timeskip is long overdue here
I'd say you should go read "Monster Duchess and contract princess" or "I am a child of this house" first before giving this a try, both do this whole schtick better despite not having the doomed future as an overarching plot point (which this one seems to have left by the wayside anyway).