WWAFA, WDWG?

When We All Fall Asleep, Where Do We Go?

That's the name of one of the most successful albums in the past decade made by Billie Eilish and produced by Finneas, her brother.

Billie wrote the specific sentence, which was inspired from her endless night terrors that she gets oftentimes when she sleeps. The whole album actually has references to her night terrors, in every song.

What do you want from me?
Why don't you run from me?
When we all fall asleep,
Where do we go?
(Snippet from "bury a friend")

WWAFA, WDWG? is not usually used in a sentence, but I've seen people asking what it meant so I thought this is the right place to do so.