You might think those are two names for one entity, for the lord of hell.

But you are wrong.

Lucifer, or, the light bringer, was once an angel and lived with god in the heavens.
God loved him the most of all his angels, for he was the first and most beautiful he created and Lucifer loved god.
The other angels envied him for gods love and thought he was arrogant, for standing higher above them in heaven.
The angel Michael fought with Lucifer one day and pushed him, so he fell down to the earth.
Lucifer called for god, he may get him back to the heavens.
He couldn't fly anymore, because his wings were broken, but god didn't answer.
The fallen angel felt betrayed, why wouldn't god hear him?
Didn't god love him, like he loved god?
Than he heard someone answer his calls, but from below the earth.

"God is to far up in heaven to hear your pleas, but I'm close to you. I can help you."

Lucifer asked the voice, that offered him help.

"Who are you and why would you help me? Do you even know who I am?"

"I know who you are, Light bringer, Lucifer. I want to help you, so that you will help me. You should know who I am, shouldn't you?"

A snake crawled toward the angels feet and stopped before him, the reptiles eyes looking into his with intelligence.

"Seducer. Satan. Never will I listen to your pretty words!"

Lucifer yelled at the snake and it retreated with the words.

"I will wait than, until you are ready."

The fallen angel wandered on earth, for centuries, still praying to god he may bring him back to heaven, but never had he been heard.
He saw gods creations, lived among them, realizing that his favored creation, the humans, were just weak creatures that struggled to live through the day so they may see another one in which they had to fight for their live again.
Killing animals for food and each other for land to live on.
Lucifer began to hate the human, they should be the top of creation?
By all means no!
They are weak, short lived , and dumb.
They were no better than the cow they held for milk and meat, and smelled like the pigs that wallowed in the mud.
Human kind should be the food for something that deserved the place at the top of the food chain.

"Are your eyes seeing and you mind open for my offer now?"

Lucifer heard Satans voice again, after centuries of silence. He answered him.

"I see it and it is horrible. Devil I want to right the wrongs, but I don't have the power for it. God turned away from me and has long since forgotten my existence. I will accept your offer and pay any price you ask."

"I shall give you the power than. In exchange you will be bound to hell and reign over one of its seven rings."

The snake appeared again, Lucifer knelt down to her and she sunk her fangs into his arm, sealing a contract with the fallen angel.
Lucifer created 3 creatures, one male and two females.
They looked the same as the human, but they were more than just that. Everything that the human missed, they had.
Strength, speed, wisdom, even abilities that were god-like, like reading others minds, or influencing the same ones.
The fallen angel spoke to his children.

"Go my beautiful children and feed from the ones that are your image, but who's eyes are unseeing. Grow in number and make earth yours."

Lucifer than retreated to hell and his children roamed free over earth.
They grew in numbers, the females having given birth to many children of pure blood and half breeds as well, so that god came to notice them and he decided to destroy the evil creation.
God ordered his angel Gabriel to find 20 humans of 18 years of age, that had a strong soul and give them the task to hunt Lucifers children.
Gabriel did as he was told and gifted the young humans with the ability to sense the evil breed and the strength to kill them.
The humans went out and annihilated almost the entire creation of Lucifer, just one missed to eradicate them from the face of earth.

When Lucifer saw this he was furious and called his son that he created to him, he gave him the ability to sense the hunters so he could hide from them and gave him another gift.
As they had only been able to spread their blood by birth, they could now turn normal humans into ones of them if they exchanged their blood.
Also Lucifer created a new female for his son and they created an army of turned to hunt down their hunters.

For decades they reigned free on earth again, until the souls of the hunters entered the circle of life again.
When they appeared again, they build an organization to hunt Lucifers breed.
They called themselves Gabriels children.
Each one specialized oneself on a weapon, that would be kept in their headquarters when the owner died, until he was reborn.

Over centuries their fight lasts hidden in nights shadows, with death on each sides, while only the souls of Gabriels children can enter the circle of life again, to hunt Lucifers breed all over again.

The Vampires, like they were called at some point, grew short in number and were almost forgotten by humankind.
And even the Hunters had lost some of their comrades.
When bitten by a Vampire and dying through the bite they seemed to be unable to be reborn.
Now only the last remaining hunters knew of the task they've been given by god and that the Vampires lived among them on earth.

It is in the here and now, when one of the oldest of Lucifers children, will come along a human, that is very different from the others.