I'd like to leave a negative rating, but keep it private, not telling the user. Is this possible? I'd like to avoid a fight, but I really am quite mad, so I'm tempted to leave one.
Unfortunately, no. If the user starts a fight, just tell him/her that they deserved it and needs to work on being more friendly on ACNL (or whatever) I have never left a negative rating though, so I don't think so