The girlfriend next door only comes to see him occasionally, so it can be inferred that the female voice next door is not sent by his girlfriend. Please bring your girlfriend over for a drink if you are free! Obviously it is polite, but it reflects that the next door thinks he has a girlfriend, but he doesn't. Neighbors also heard strange female voices. Where does the strange female voice think I have a girlfriend? Walls? I remember handling a case of dismemberment before, and the MP3 player of the deceased made a sound and was found.