Blackground Character

The black character or characters on a tv show or movie that will inevitably die, and usually has no real significance to the plot other than to die.

"Yo, all the black characters get eaten by the zombies"
"Yeah dude, they're just blackground characters"

blackground singer

A group of stereotypical black gospel singers who back up another genre of music.

Rick Astley's voice is quite low in the song "Never Gonna Give You Up", good thing he had those blackground singers to balance out the song.