The truth of these monsters are based off a legend of a woman who a mistress of Zeus. She was cursed by Hera to devour all her own children she had with Zeus. As a result, she was transformed into mothering a race of creatures which breathe life into modern, vampiric tales.
The mother of the Drakaina was originally a queen of Libya named Lamia who eventually became a mistress of the god Zeus. For her treachery, Hera, Zeus' jealous wife, killed all of Lamia's children, the Lamiae. She then cursed Lamia to be transformed herself into a monster that hunts and killed others. Lamia embodies the idea of one who is treated monstrously and out of grief and despair becomes a monster herself.
Many myths go on to describe the special attributes to the Drakaina regarding eyesight. The original curse said they were unable to close their eyes and such found the bright light of day to be painful, and so they were driven to seek the shadows of night. However, it is said they eventually removed their own eyes and in exchange for the loss of wordly vision gained the heightened senses of prophecy.
In reality, the Drakaina are indeed demons of night, but their speed, ferocity, and powers are derived from abilities to sense several moments into the future, passed down from the prophetic skill of their mother, Queen Lamia. For this reason, they are notoriously difficult to trick or destroy. In myth, it is said only the power of a god or demigod, a channeler, could destroy them.
The word drakaina references a female python or dragon, the feminine of drakon. A title given to the Lamiae for their grace as well as their poisonous fangs.
Today they lurk in darkness and hunt, bloodthirsty and merciless. Their male counterparts are the Dreyken.