@crunchberry That and IMO more importantly, there's way more foreshadowing in this. You don't just drop something like that in as a twist out of nowhere. My problem with Usagi Drop isn't that it happened at all, it's mainly that I was like "I don't believe a frame of this. Neither of them ever felt like they had feelings different from father-ish/daughter-ish for each other, and they still don't now that they're supposedly getting together, plus he totally had the hots for that nice lady nearer his age with the vavoom body. This didn't come out of left field, it came from outside the stadium!"
So I'm fine with it if they sell it--if it has some groundwork laid, if it feels in character, if the emotion comes across. In Usagi Drop it was the opposite--it felt forced, had no buildup, no feelings, and just basically felt like the mangaka wanted a shock twist ending and used the characters as marionettes to get it. To be fair both MCs in Usagi Drop were so low-key and unemotional that it would have been hard to put strong romantic feelings across at the best of times--but that's all the more reason if you want to make readers dig that they're feeling unexpected emotions you have to put some work into it.