Exile Vilify

"Exile Vilify" is a song  Originally, it was intended as a “fake ending,” where the player would find a hole in the roof of Aperture Science, and the moon would be visible. The player would shoot a portal at the moon and would be sucked in. Once the player dies, credits would roll, and “Exile Vilify” would play in the background. This easter egg, however, was removed, due to how playtesters easily overlooked it.

The whole song evokes the relationship between Chell and GLaDOS as the former navigates the rebuilt Enrichment Center.

Lyrics
Note: The bolded part are in Rattmann's scribbling

GLaDOS

 * "Does it trouble your mind the way you trouble mine?" - GLaDOS has conflicted feelings about Chell.