Aurora – First child of Adam and Eve, born before the fall of mankind, who was lost from Eden and began a line of descendants born without Original Sin who came to be known as Anabo.

Mephistopheles – The dark angel of death who ferries souls bound for Hell. He is Lucifer’s second in command, and has many thousands of minions to aid him in his work.

Elektra – An Anabo Mephistopheles fell in love with over a thousand years ago. She bore him seven sons, in secret, without God or Lucifer’s knowledge. Before her eldest was compelled to jump to his death and be resurrected to immortality, he murdered Elektra to release her spirit and alert God and Lucifer to the existence of his younger brothers, to save them from his fate of losing all light in his soul. The remaining brothers were blessed by God at death, ensuring they retained the light of Elektra when they came back as immortals.

Mephisto – Six immortal brothers, sons of the dark angel, Mephistopheles, and the Anabo, Elektra. Their sole purpose is to capture those who’ve pledged their souls to their oldest brother, Eryx, and imprison them in Hell on Earth. By virtue of the blood of Mephistopheles, they are bound for Hell when the world ends, or when Eryx is finally defeated, unless they fulfill the Mephisto Covenant.

Anabo – Pronounced uh-nah-bo. A human born without Original Sin. Extremely rare. An Anabo may be recruited to be a Lumina, or she can become Mephisto via a change in DNA when she’s kissed by a Mephisto. If she’s immortal, the change to Mephisto is permanent. If she’s not immortal, she can ask Lucifer to be returned to how she was before the kiss. If an Anabo wishes to become like other humans, she can request to lose Anabo and Lucifer will make it happen.

Eryx – Eldest brother of the Mephisto, oldest son of Mephistopheles, Eryx lost all light in his soul when he became immortal. An anomaly, his soul belonging to neither God nor Lucifer, to fill the hopelessness within, he wants to take the reins of Hell from Lucifer and thereby control all of mankind and eradicate free will, dooming all humans who are not Anabo to Hell.

Lucifer – Ruler of Hell, the down to God’s up, dark to the light, he is mankind’s conscience, the reason for free will. Mankind is fallen and have the choice to rise above it, or not.

Lumina – Exceptional humans with extraordinary light in their souls, recruited by the Mephisto to become immortal and live and work with them on Mephisto Mountain. A recruit dies and is resurrected by God to be a live angel. Luminas may marry other Luminas, but are discouraged from interacting with humans.

Purgatory – A spirit meant for Heaven, but unable to ascend because of their anger at God, usually because of something occurring just before or during death. They are sent to work for the Mephisto to learn humility, acceptance and forgiveness from the Luminas.

Hell on Earth – A labyrinth of caverns deep within the Earth, carved out by Lucifer to imprison those who pledge their souls to Eryx.

Lost soul – One who pledges his or her soul to Eryx. Upon death, their soul is absorbed by Eryx, making him stronger. When he believes he is strong enough, he will declare war on Lucifer and attempt to take over Hell. The Mephisto and Luminas know the lost souls by the shadow across their eyes. If captured, they die in Hell on Earth, their spirit unable to escape and add to Eryx’s strength.

Skia – In Greek, skia means shade, or shadow. Skia agree to become immortal followers of Eryx, and hand their soul to him upon resurrection. They are drones, incapable of free will, enslaved to Eryx’s commands. The Skia are Eryx’s recruiters, and search constantly for humans who are vulnerable, who are likely to pledge their soul. The shadow across Skia eyes are much darker than the lost souls because their spirits already belong to Eryx. Unlike the lost souls who die when they’re sent to Hell on Earth, the Skia are immortal, and live in eternal misery and horror if they’re captured. They have strength equal to the Mephisto and are specifically chosen by Eryx for their exceptional intelligence, which makes them cunning and more difficult to capture.

The Mephisto Covenant – God’s promise to the Mephisto of redemption if they win the love of a woman and selflessly love her in return. They are limited to extremely rare Anabo females because human girls are afraid of them.

Kyanos – A small island in the North Atlantic, surrounded by a mist created by Mephistopheles over a thousand years ago to hide Elektra and his sons from God and Lucifer. When the youngest Mephisto became immortal, they left Kyanos, but still return for councils, or for punishment.

Council – A meeting of the Mephisto on Kyanos, a trial of sorts to determine guilt and punishment of a Mephisto who’s broken a hard rule. Punishment is usually a period of solitary time on Kyanos, which is primitive and cold.

Mephisto Mark – An internal mark made by a Mephisto to an Anabo during sex, allowing the Mephisto to mentally search for and find her, as they do with each other. If the Anabo is immortal, the mark is permanent. If she’s still human, it is not and can be replaced by another mark, or erased entirely by Lucifer.

Scent – A particular scent attached to an Anabo, Lucifer’s way of indicating which Mephisto she is meant for. If an Anabo is found and any of the brothers could go for her, it would be a free-for-all, a fight to the death – and they can’t die. To keep order, Lucifer attaches a scent to an Anabo, and the Mephisto who don’t catch it are instinctively not attracted to her.