Assassin of "Black" ("黒"のアサシン, "Kuro" no Asashin?) is the Assassin-class Servant of Reika Rikudou of the Black Faction in the Great Holy Grail War of Fate/Apocrypha. Originally summoned by Hyouma Sagara, Reika becomes her Master shortly after. She is one of the Servants of the Protagonist of the Grand Order conflicts of Fate/Grand Order.