Lyric discussion by TheAwkwardSwan 

Cover art for BYOS lyrics by Regina Spektor

I thought it might be one of Regina's Holocaust songs.

The singer doesn't agree with the Nazis, but they're forced into it. They go along with what they're told to do, because they feel they have no other option. They meet Mata Hari, and they sympathize with her situation. They carry out orders mindlessly, burying bodies, digging up wells, cutting hair and bones and hating every minute of it, but unable to escape.

The lines, "well I thought I'd do something nasty as well," and "my invitation said bring your own shovel" has the same tune as the line "brown paper packages tied up with strings," from the song "My Favorite Things" from "The Sound of Music." I thought the reference might be there for a bit of sarcasm, as though to say that the singer is NOT doing their favorite thing, and they detest their own word. Then there's the sarcastic Elvis reference with "Darling I'm all shook up now," inferring that the singer is indeed "shook up," but not because of any love for their job. Quite the opposite.

Perhaps I'm being too morbid though.