I'm a librarian who loves anime, manga, and reading a wide variety of genres.
Yayoi has killed her husband (not a spoiler - it's mentioned on the back of the book and happens fairly early on). So far, responses have gone something like this:
Yayoi: I don't know what to do. Masako can you help me?
Masako: Sure. Don't worry, I'll take care of everything. (Me: ::too stunned by the instant offer of body disposal help to even sputter::) Hey Yoshie, you borrowed money from me. Want to pay me back by helping me out with this one thing...?
Yoshie: OMG, what is wrong with you??? You should call the cops. I don't want any part of this. Wait...you mean I can have the money in his wallet? Okay, I'm in.
Kuniko: So, Masako, since you gave Yoshie money I was thinking maybe I could borrow some from you too....
And some guesses for the future: