"Shadow Demons are everywhere. In every shadow that you see, one or more Shadow Demons will be residing in them. You humans simply cannot understand how dangerous they can be and you never will. Piss a Shadow Demon off and you will never see the rest of your life or the light of day again."
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It is unknown to how long Shadow Demons have been around, but it's most likely that they have been around since the time of Adam and Eve. Due to Adam and Eve being the first people on Earth, Itzel Erebos had formed in the shadow of Adam whereas Senka Kerrin formed in Eves. Itzel and Senka took their time in understanding why they had been formed and to also figure out their powers. They were unable to use their powers for many years, not until Adam and Eve were no longer living. Throughout that time, one of many Shadow Realms had been slowly creating itself and thus this was a place that Itzel and Senka fled too.
As more and more humans were born into the world, Shadow Demons continued to form. Scientists believe that the Shadow Demons formed through the fear of the humans but that theory is unknown. However it is known that Shadow Demons do often feed off of the humans fear. For the humans, they are unable to see the Shadow Demons unless the demon itself let's them.
Itzel and Senka stayed in the Shadow Realm which is a parallel universe to Earth, watching as the years went by. Time moved the same way as it did in universe of Earth. It wasn't until they grew tired of watching the other demons that Itzel and Senka had chosen to leave their realm and go back into the shadows of a human. It took them several years for them to finally choose a human before they possessed them. Itzel had chosen to possess a young boy at the age of seven by the name of Elliot Rouge.
Elliot Rouge was a born that had been born into an abusive family. His father was a drunken alcoholic and his mother was always stoned out of her mind on drugs. To this day it is still unknown to Itzel to why he had chosen Elliot for a vessel. At the age of seven, Elliot began changing and his parents noticed. Instead of cowering in a corner in fear, he would fight back. Itzel had been living in Elliot's shadow since the day he had been born. This wasn't anything unusual considering many Shadow Demons done the exact same.
At the age of twelve, Itzel had killed of Elliot's mother. After Molly Rouge passed out, Itzel had injected more drugs into her system which eventually lead to Molly overdosing. She never did waken up. Itzel had fled back into Elliot's shadow when the police had came for the simple fact that Itzel felt as if he was going to have to find a new shadow to live in if the police arrested Elliot. Fortunately, this never happened. Elliot didn't get the blame. The police had just confirmed that Molly's death was indeed from an overdose of the drugs she had been taking.
It took until Elliot was twenty-six that Itzel possessed him once again. After Molly's death, Mickey Rouge's drinking got heavier and heavier and thus the abuse got worse. Elliot often ended up in hospital and sometimes even close to death. Mickey was killed by the Shadow Demons – all his limps had been pulled apart leaving the living room looking like a blood bath. The police never found Micky's body as his body had been taken into one of the Shadow Realms and turned to nothing but ash.
Itzel stayed in Elliot's body, taking it as his own. The real Elliot never returned. Elliot had became a vessel for Itzel.
Considering that Itzel and Senka had been the first Shadow Demons in the Shadow Realm, they were considered as the king and queen and to this day, they still are. Although Shadow Demons have minds of their own, whenever Itzel and Senka summon them, they are under complete control of their king and queen.
The Shadow Realm is a place of darkness, a place that Shadow Demons find safe. Unlike humans, Shadow Demons are very capable of seeing perfectly in the dark whereas the light damages their eyes. Each and every Shadow Realm had been created differently and so had the Shadow Demons.
Shadow Realms each have their own element, the main ones being; fire and water. Like the human universe, there is also a prison for demons who are beyond uncontrollable and unstable for living in the shadow of humans or even being in the humans world.
Each Shadow Realm opens one at a time if the Shadow Demons need to enter or leave, but if spoken the true names of their king and queen, every Shadow Realm will open at once, leaving nothing but chaos.
Itzel Erebos is the true name of their king although no one apart from the Shadow Demons know this as since Itzel moved to staying on Earth, he had been continuously going by the name of Elliot Rouge – the human vessel that he had possessed. Senka Kerrin, the true name of their queen, had possessed a girl by the name of Lily Hillingon. Both names should never been spoken. If every Shadow Realm opens all at the same time, hell is sure to consume Earth and it would be impossible to stop the Shadow Demons from killing and possessing as they would be out of the control of Itzel and Senka.
Although Shadow Demons are created from shadows, they do possess powers. Many of them differ from others. When it comes to the realms of fire and water, those Shadow Demons are capable of controlling anything that has something to do with those elements.
It is not unknown to any species that the Shadow Demons would sacrifice their lives to save their king and queen. This has happened time and time again throughout the years as many species, including humans, have tried to harm or use Shadow Demons for experiments.
When a Shadow Demon has possessed a human, the human no longer has a shadow. Other humans are unable to notice that the possessed human doesn't have a shadow only other species are capable of identifying a human that is possessed.
It is unknown to how well Shadow Demons are at controlling their powers, but apparently they have no problems with them excluding the fact that newly formed Shadow Demons end up staying in the Shadow Realm until they are able to control their powers. The three main powers that every Shadow Demons has consists of teleporation, realm crossing and possession. For Itzel and Senka, they possess two more powers than the average Shadow Demons which is summoning the Shadow Demons and controlling them along with being able to create smokescreens. Due to neither Itzel nor Senka living in the fire or water realm, they do not possess those two powers, but they also do not need to. Itzel and Senka can control any Shadow Demon from any realm.
When it comes to Shadow Demons, they are unable to die like humans. Shadow Demons can be around for many years and never look like they are getting older. There are ways to harm a Shadow Demon, but only if they are in the form of a human. Although there is an exception if the Shadow Demon isn't in human form. If they are living in the shadow of a human who get killed, the Shadow Demon will die off as well and will be unable to return. A few ways of killing a Shadow Demon in human form is electrocution and decapitation. As Shadow Demons do not have a beating heart, being stabbed through the area the heart resides in will not affect them.
The main way to kill a Shadow Demon is through exorcism. Unfortunately using this way to get rid of the Shadow Demon will also kill the person performing the exorcism along with the human vessel that the Shadow Demon possessed. There is no specific way for the ritual of exorcism to be performed although usually it would involve a priest and a church. If a Shadow Demon is exorcised, other Shadow Demons will be able to sense it and it will weaken them for a short amount of time. Each Shadow Demon is capable of seeing through other Shadow Demons eyes before the Shadow Demon is exorcised. Thus this gives the Shadow Demons a view on any other people who had been around for the exorcism. It isn't uncommon that Shadow Demons will avenge their fallen brother or sister by taking out anyone who had been in the same room or even in the same vicinity as the deceased Shadow Demon.
Senka Kerrin/Lily HillingonEdit
Senka was the second Shadow Demon that had been formed through Eve's shadow and the only other Shadow Demon that Itzel truly trusts. They had spent many years together, getting to know one another and helping each other to gain control of their powers. Throughout the many years they spent together, Itzel and Senka are never really that far away from one another. After Itzel had possessed Elliot and Senka had taken over Lily's body, they had met many years later and continued on with being with each other. The Shadow Demons know very well that their king and queen are never too far afield from one another as Itzel and Senka tend to draw power from each other when need be. Unfortunately after several long years of being together, they were split apart forever. Someone had found out about Senka and a priest had been called in to exorcism her. For Itzel, he had sensed this and so had all the other Shadow Demons. Senka had been exorcised and the priest and Senka's vessel died. Every Shadow Demon saw their queen being killed and felt it. Through the eyes of their queen, they were able to see everyone else that had been in the same room as Senka. Itzel and the other Shadow Demons took their revenge by killing everyone that had been in the same building as their queen. Itzel had lost his dearest friend and wife. On that day, Itzel had lost a part of him which made him angrier than normal especially if Senka is mentioned.
Cascade Le BlancEdit
It wasn't until after Senka had been killed that Itzel had met Cascade. Itzel didn't trust humans, not in the slightest, but this changed when Cascade entered the picture. Itzel did not fall in love with her, but in fact found her quite interesting. Cascade was freelance assassin and currently to this day, still is. Cascade had somehow found out that Itzel possessed Elliot considering the fact that Elliot Rouge had been Cascade Le Blanc's childhood friend and she had definitely noticed the changes in Elliot. Cascade had confronted Itzel and managed to get some information out of him. Instead of calling a priest or doing anything else that would harm Itzel/Elliot, Cascade remained friends with him instead. This was something that surprised Itzel, but he did not complain and Cascade had also come in handy. Even though he had spent many years of Earth acting like a human, Cascade had begun telling and showing him how to act more human than he was. Although Itzel is a Shadow Demon, he does act like a human to remain alive and not to end up with the same fate as his dear Senka. With Cascade being an assassin, Itzel began helping out and this worked well considering it let him release his anger. Itzel is quite protective over Cascade and vice versa.