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Intro. Albedo (アルベド, Arubedo) is the supervisor of the Floor Guardians, in the Great Tomb of Nazarick. She is in charge of the general direction and oversees the activities of the Guardians of the Seven Floors, which means that she stands above all other NPCs in Nazarick. She is the sister of Nigredo and Rubedo. It was created by Tabula Smaragdina.

Albedo (Version: season 4, episode 2)

@Alex