Buffy run away with Spike after end of season 2. After much traveling they settle down in St Petersburg and start martial arts school. Joyce runs shelture for demon in her own house. And one day gets photoalbum full of happy Buffy photos. Buffy & Spike mated and they expecting child it had something to do with mating. I believe Tara and Anya know there they are and call them for help. After another big bad deafit they leave with out notice back to they home. I also remember episode there Spike tells Angel how all they property always on Buffy's name to keep unwelcomed vampire guest out
