The Three Furies, The Beginning...

How it all began.
The Erinnyes were "the Angry Ones", known as the Furies in Roman. They were the feared avenging goddesses in Greek and Roman mythology who were born from the falling drops of blood of Uranus (Sky) when he was mutilated by his son, the Titan Cronus. The drops fell on Mother Earth (Gaea) and impregnated her.

"...and Cronus cut off his father's genitals and threw them into the sea; and from the drops of the flowing blood were born Furies, to wit, Alecto, Tisiphone, and Megaera." Apollodorus, Library and Epitome (ed. Sir James George Frazer)