Norns

Norns ("nornir") are three female spirits in Norse Mythology who spin the thread of every human life's fate. They are known by the names of Urðr ("Wyrd"), Verðandi (Verdandi) and Skuld. They are mentioned by Arvid in S2/E1: East vs West.

Trivia
Those three "sisters" also appear in other beliefs and stories. In ancient Roman Myth they are known as Parcae and the ancient Greek knew them as Moirai. William Shakespeare gave the three Witches a role in "Macbeth" and Terry Pratchett placed them in several of his "Discworld" novels as maincharacters. In the game series "The Witcher" the inhabitants worship a goddess named Melitele, who also is displayed in shrines all over the game as three women (Maiden, Mother and Crone). A less friendly trio of women appears in "The Witcher 3 - Wild Hunt" as the "Ladies of the Woods".