Wasn't it proven near the end of Usagi Drop that the girl and old man weren't related by blood? And even the old man knew that fact waaaay early-on after seeing her 'baby diary' or whatever it was called that proved her lineage.
Still, yeah, these two stories fell under the same plot that revolved around the old Japanese story 'The Tale of Genji', involving the 'father-figure' of the story literally marrying and/or consorting with his adoptive daughter, which you can imagine didn't receive good reviews from western audiences.
It was, but you can't expect people who lost interest to know that.
Not exactly. In "The Tale of Genji" the MC was the one who decided to start a relationship. In those two stories it was the other way around and the male MCs just accepted it. Though I can understand that the (western) audience felt jebaited by "Usagi Drop", since the author seemingly set up love interests for both of them, comparing the two stories is kinda disingenuous.
The thing with these stories is that, whilst going by standard western morals it's squicky at best, you could also make the statement that people who (seemingly eternally) rage about it are infantilizing the female MCs by disregarding that it's their choice to try and start a relationship after becoming adults and the selected partners choice to accept. It's the date range bullshit all over again. Once two people are adults, save for some specific circumstances, the relationship between them is their business only and the best one can do is limit the damage done, if it's really turning bad.
