This entire post is basically one huge spoiler, so please be cautious when reading, especially if you haven’t read volume 21 yet.
Although volume 21 of Nana brought the series to what could have been a dramatic finale, the series is actually on hiatus because Ai Yazawa was being hospitalized for an unknown illness. The manga tells two stories: one of the present day alongside brief glimpses into the future. However, with the series unfinished, there is a gap left between the present day and the future, so many questions have been left unanswered. When did Nana Osaki leave all of her friends behind to go to England, and why? What happened to Black Stones and Trapnest after Ren Honjo’s death? And what happened between Hachi and Nobu? But the biggest question I think many fans want answered is who are the parents of Ren and Satsuki? I have a few thoughts about this subject, but please be aware that my opinion is pure speculation and that there is no right answer as long as the series remains unfinished.
I’ll start with Ren, the boy we see with Takumi in England in volume twenty. This may get confusing because there are two Rens: Ren Honjo, Nana Osaki’s boyfriend who dies at the end of volume twenty, and Ren the child, so from now on I’ll be talking about the latter unless I use Ren Honjo’s full name. Even though Ren calls Takumi ‘daddy’ and Hachi asks where he is during a phone call with Takumi, many fans do not believe that Ren is the child of Hachi Komatsu and Takumi Ichinose. When Hachi got pregnant, she had just broken things off between her and Takumi and began dating Nobu. However, when she realized she was pregnant, she and Takumi got engaged even though she loved Nobu because she believed there was a greater chance that the baby was Takumi’s (since he didn’t use protection). The fact that Ren has light hair has led many fans to believe that Ren is actually Nobu’s son with Hachi. As for my personal opinion of this theory, while I do think it would make for great storytelling that Hachi dumped Nobu because she thought she was having another man’s baby, just for that baby to turn out to be his, I really don’t believe that Ren is Hachi and Nobu’s child. Just because Ren has light hair doesn’t automatically mean he can’t be Takumi’s son, especially since Hachi has light hair as well. At the beginning of volume 20, Ren is very cold to Takumi, which reminds me of Takumi’s coldness toward most people. Naoki even comments that Ren has Takumi’s “evil eyes,” and thus for these reasons I believe that Ren really is the son of Takumi and Hachi. I wouldn’t be surprised if I were wrong though – after all, this is Ai Yazawa we’re talking about.