The Fates were three Roman goddesses known to the Greeks as the Moerae. They were also called the daughters of the night, suggesting some connection with the dead. However, at some stage they got bored with the dead and started focussing on the fates of the living.
They are supposed to spin a length of yarn that represented the life span of the applicable mortal. Even the mighty Zeus, the chief Greek god, was subject to the decisions of the Fates.
They are accompanied by the Keres (the Dogs of Hades); three creatures with sharp teeth dressed in red robes. You can honor them with gifts of honey and flowers.