The rei ayanami expy is a character archetype common in Japanese media. Started, or at least codified, by Rei Ayanami from Neon Genesis Evangelion.

Common characteristics of the archetype include:

.Love interest. .Dark, mysterious, tragic and otherworldly origin. .Pale skin, unnatural hair and eye colour. .Appears and acts quiet, stoic, emotionless, talks in monotone. .Is a robot, alien, clone or artificial human. .Suffers from an illness or major injury. .Occasionally has a strong connection to a parental figure, boss and/or antagonist, and may even display Undying Loyalty to them. .Eventually becomes more emotional, or turning out to have a Sugar-and-Ice Personality.