Death (mythology)

A pale girl with dark hair attended Bernice Summerfield and Jason Kane's wedding. She was around the age of fourteen, dressed in black clothing, and carried a red rose.

Bernice Summerfield asked if she knew her, and the girl said it was "[her] job to turn off the lights once everybody's gone" and that Bernice would meet her "one day". (PROSE: Happy Endings)

Behind the scenes
Paul Scoones of the New Zealand Doctor Who Fan Club reported that Cornell had told him the girl was Death of the Endless from Neil Gaiman's DC Comics series. However, Neil Penswick, who wrote the relevant section of Happy Endings, told the fanzine Broadsword that the character was not Gaiman's Death, and said only that "The girl has appeared in other works."