Assassin in the anime Outlaw Star who kills by twilight, hence her nickname. After Gene Starwind thwarts her efforts to kill Fred Luo, she vows to kill him, later negating these efforts and joining the Outlaw Star crew instead.

Briefly, "the realization that each random passerby is living a life as vivid and complex as your own." Originally from the Dictionary of Obscure Sorrows, which has a lot more beautiful neologism definitions like this you might enjoy.