Nightingales are members of the fabled Nightingale Order, a coven of elite thieves, whose existence is a myth even among the Thieves Guild. The most recent members of this order were Gallus Desidenius, Mercer Frey, and a Dunmer named Karliah.
Nightingales act as guardians of Nocturnal, the patron Daedric Prince of thieves, and her shrines. In return, Nocturnal grants the guild good fortune and the Nightingales various powers of stealth and shadow.
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