The Keres were the opposite of the Greek mythological spirit Thanatos, The god of peaceful kind of death. The Keres were demons or female spirits of violent or cruel death, murder, accident or ravaging disease. They were agents of Moros, the demon god who drove people to their unavoidable destruction, and the fates, who measured the length of a persons life when they first entered world. After ripping a soul free from the mortally wounded soldiers on the battlefield and sending it straight to Hades, they feasted on them due to their cravings for blood. Thousands of Keres haunted the battle fields, fighting amongst themselves. The Keres had no absolute power over the life of men, but in their hunger for blood they would seek to bring death beyond the bounds of fate.
The Keres were portrayed as taloned, fanged woman who wore bloody garments. They had been one of the few evil creatures to have escaped Pandoras jar to plague man kind. They are the daughter of Nyx Moerae, and punish men for their crime, according to the Greek poet Hesiod in the seventh or eighth century.