Heaven

"Wherever I was, I was happy. At peace. I knew that everone I cared about was all right.  I knew it.  Time didn't mean anything, nothing had form, but I was still me, you know?  And I was warm and I was loved and I was finished.  Complete.  I don't understand about theology or dimensions, or any of it really.  But I think I was in heaven."

- Buffy

Heaven is a name applied to an afterlife dimension. There are believed to be billions of heavenly dimensions.

Description
Heaven is an afterlife where the souls of human beings go after they die. Buffy Summers once returned from a place she believed to be heaven, and the resulting shock of returning to Earth caused her to suffer from severe depression.

Cordelia Chase spent time on a higher plane, similar to, though not confirmed to be, heaven. She grew bored and eventually returned to Earth. It later turned out that she had only been sent there so that Jasmine could travel with her to Earth.