While I can see why Main's story might be interpreted as that of a young Ubume, this seems to be contradicted by an actual flashback/nightmare in the last pages of chapter 1.3. There, Ubume is in shock at the sight of Tanuki's massacre, dressed in a high school uniform (so about Main's age), and her facial features are exactly the same as in the present. Now, that might be misdirection or retconning on the author's part, but it seems highly unlikely.
I'm always struck by how topical Asano's choice of subject matter in this manga is, in a ripped-from-the-headlines kind of way. We had the Megiddos arc just as
the real life Johnny's saga was unfolding, and what do you know, now that the Japanese government is
cracking down on host clubs because female customers are resorting to prostitution to pay their exorbitant charges, there is a host club/enjo kosai storyline.
This seems to be similar to Dededede, in which (as per his interviews) the ending was not determined in advance and he's just making it up as he goes along. I for one am all for it if it means more insights into the rot at the core of modern Japan.
As always, thanks to the team for their excellent work and my condolences to BaganLee.