The secret files of Miss Saeki

Did any of you happen to imagine what was written in the burned secret files of Miss Saeki in Kafka on the shore?

“Nakata understands,” he said, nodding seriously. “If that’s what you’d like, Miss Saeki, I’ll be happy to burn it all up for you. You can rest assured.” (Kafka on the Shore, Ch.42)

I happened to imagine it was depicted in the Tony Takitani film when I saw Rie Miyazawa who doubled the parts of the wife and the assistant in the film, as well as played Miss Saeki in the theatrical adaptation of Kafka on the Shore.