Reoccurring characters in "Revolutionary Girl Utena" that are known for comically sharing the events of Ohtori Academy with each other.
Shadow Girls C-Ko, E-Ko and F-Ko have no clear origin, but they are three high school girls of Ohtori Academy that appear randomly and spread the facts or rumors of the events around the entire campus.
The girls debuted in the Student Council Arc of the Revolutionary Girl Utena series and according to the its director, the shadow girls were based on stage characters that were never meant to be seen by the characters, but by the viewers instead.
Revolutionary Girl Utena: Adolescence Apocalypse
A alternate retelling of the Utena anime.