So as a nana fan myself, I've come across some pretty interesting opinions of the anime and its characters... One of the most popular opinions shared by most fans, is that Hachi belongs with Nobu and not Takumi. Now I know it might seem logical to think this way, given that Nobu is a sweet guy who treats Hachi right and Takumi is very... how do i put it... controversial? I mean the man is obvs a womanizer and even r*ped her... but I don't agree that she would have been happier with Nobu.
First of all, Nobu has a savior complex. He idealised Hachi and saw her as a victim in a cruel world who needed saving. He never saw her for what she truly was like Takumi did, and she felt as though she was accepted when she was with Takumi.
Second, she wouldnt have been as happy with Nobu if they persued their relationship, due to the fact that she mentioned multiple times that she doesnt want a man that will treat her right because of what happened with Shoji. She was hurt by getting cheated on and it is understandable that to some extent she would close her hart off to avoid getting hurt again. So it makes sense why she should be with Takumi instead of Nobu as it wouldnt be very likely that she would fall deeply in love with him.
Finally, Hachi needed that harshness and rationality of Takumi to ground her. She was immature and she knew that. If she were to be with Nobu, she wouldnt have grown as a person as the two of them are too similar.
Whew... feels good to get that off my chest lol
kiss kiss kiss