Also known as: セルリアン(けものフレンズ), セルリアン, cellien
The primary antagonists of the Kemono Friends franchise. They are a hostile and invasive species formed from either the fusion of Sandstar with inorganic material, or from a material known as Cellium which copies the shapes of objects. They are known to devour Friends, though they do not kill them but rather return them to animal form and permanently erase their memories.
"Cellien" was initially mistranslated as "Cerulean" in the Crunchyroll subtitles, so most English-speaking Kemono Friends fans know them as such.