[[WMG:Kana will finally be able to "move on" when her life with Daikichi is over.]]
She doesn't know why she stayed a ghost after she committed suicide, but the hints are that she did kill herself because she was desperately lonely. Now that she's found Daikichi, she will have "fulfilled" the reason for her having been stuck on earth as a ghost. By the end of the series, she not only says she has lost her fear of the living, but also that she has lost her fear ''of'' living. Significantly, Daikichi is wondering to himself if there is any way he could make Kana alive again when she looks over at him and says "It's great to be alive, isn't it." When Daikichi finally dies, she will be able to go with him. (I certainly hope so anyway because the alternative - that Kana will remain on earth as a ghost without her most beloved - is too heartbreaking to think about.)
[[WMG: Kana and Daikichi will live at the apartment forever.]]
A reverse of the previous WMG. Instead of Kana moving on when Daikichi dies, he becomes a ghost and together they haunt the apartment, which may or may not have gotten some new residents by then
[[WMG: That horrible old man was an angry ghost.]]
He certainly didn't look of this world, and it would explain why he knew Utako was emotionally vulnerable and preyed on her while her defenses were down. He's just some hateful spirit that died angry and now spreads it around.