is she in love with the father-in-law?

I think so, they were in love with each other. At least that's my interpretation of it. At the end, when he tells her "The only thing I can do is free you" and says that he will soon retire and live with his wife until he dies, as to remind himself and Kikuko that he's too old for her, I took it as the confirmation. But I might be wrong. I suppose it's pretty much left open to interpretation.

Language! The thing that means stuff.

In the book that this is based off of, it is said that Shingo had a "fatherly yet erotic attachment to Kikuko."

There is no way to tell for certain but I feel like if they tried to follow the vibe of the book, the father-in-law at least had some sense of attraction to Kikuko.

Yes.

Or maybe a relationship based on intimacy and understanding. An attraction yes, but unlikely erotic. Maybe he is attracted from her kindness and genuineness.


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