Hi guyssss :D
There were a lot of terms from the first chapter that didn't make sense so I'm gonna explain them nowwww~
sorry that I can't integrate the explanations into the story to make it more interesting ):

I will also include Character info~

Just ask me if there is something you don't understand! :)

On a side note, did you guys saw Momo's vampire stage at 'Hit the Stage'?
My reaction was "I CAN'T! TOO MUCH FEELS! MY BODY ISN'T READY" lol
she was making everyone thirsty ;D
Btw Momo isn't a vampire in my story

Demons

When humans experience a negative feeling, they emit dark energy. And the accumulated dark energy becomes a demon.

There are 7 demon ranks: E rank, D rank, C rank, B rank, A rank, S rank, SS rank.

E and D rank demons are relatively easy to beat because they are weak, but it’s still difficult for a human to defeat it. When they die, their corpse will disappear

C rank demons are harder to beat. And starting from this rank and above, the demon's corpse will not disappear by themselves. If left for a long time, then the corpse will come back to life.

Rank A demons rarely spawn around/in the city, but usually spawns near the 'Ater Zone'. (And that is also rare)

Rank S demons will almost not spawn outside the 'Ater Zone', one usually spawns every half a year.

There is only one recorded SS rank demon in history; and they could not defeat it, only seal it. The location where the demon is imprisoned is highly classified, only a handful of people know where it is.

Humans

They make up 50% of the world population.

They are weak and they don't have any super powers.

Some of them however are a bit special. Their blood is much more enchanting/attractive, and they don't only attract Vampires but also the other supernatural species. These types of humans are called Sirens; and 8% of the human population are Sirens. 

Supernatural species also normally don't have any special abilities. But if Siren becomes one of the supernatural species, they would gain a special ability. And when they use their ability, their eyes change color. But other than that, there are no distinguishable physical feature between a normal supernatural and a Siren supernatural.

Vampires

Same old vampire from stories. Make up the 20% of the world's population.

These ones can walk in the day light.

They used to hunt humans for blood, and some of them still do. But now it is thought to be savage to do such thing, and they just buy blood bags from hospitals.
And yes, buy. That means they have to work too in some way.

'Those who don't work, do not eat.'

The primary Vampire clan in Seoul are the Royal Im family. Aside from that, they are also the number one vampire family in South Korea. Owning the enormous​s and successful Im Corporations and Im Hospitals. Their hospitals are all over South Korea; the headquarters being in Seoul. They are known to be the strongest, smartest, and most resourceful of all the Vampire Clans in S. Korea.

Their leader is the Vampire Queen. (The King had died)

If a Siren Vampire uses their ability, their eyes become the color blue.

Trueblood Vampires are direct decedents of the first vampire, Vladmir. They have orange eyes instead of the usual red eyes.

Werewolves

They are the same ones from the usual stories. Also 20% of the world's population.

They are the ones that can easily blend into human society, as their skin isn't deathly white nor do they have to eat a specific type of food.

Most of the werewolves still hunt their own food, however they sometimes still have to buy from supermarkets (because they don't want to over hunt the animals).

The local werewolves are the Royal Park Clan, and yes they are also the number one clan in S. Korea. They own most of the amusement parks and zoos all over the country; they also own one of the biggest entertainment corporation, JYP Ent. Despite being working for Werewolves most Korean entertainers aren't supernatural creatures.

Their leader is the Wolf King.

If a Siren Werewolf uses their ability, their eyes become green.

Trueblood Werewolves are the direct decedents of the believed first Werewolf, Fenrir. They have orange eyes instead of the usual yellow eyes.

Eaters

They make up 10% of the world's population. And only 2% of them are natural born eaters, the other 8% are all turned Eaters.

They all have a bracelet on their dominant hand, and those bracelets cannot be removed; if they do remove it, they will die. Natural born Eaters will start wearing their bracelet the moment they are born. If a normal human wears the bracelet they will become an Eater.

All Eaters have their own weapon based on their personality, and they can only summon their weapon using a personal scabbard. They have to form a contract with a scabbard to make it personal; it is done by giving it a moderate amount of their own blood.

They are the only ones that can completely exterminate a C rank and above demons. They are able to do this because their weapon has a 'predator' mode, where the weapon 'eats' the demon.

They have the ability to teleport, however it is extremely hard to control it; and if done recklessly can lead to serious injury. However, they can only teleport within a range, and the more powerful an Eater is, the bigger the range. The main Eaters in the story has a range of 20 m.

Eaters cannot eat normal food. They have to eat raw food; their body will immediately reject any processed food (they would throw up). With the exception of dairy products as long as they aren't mixed up with other ingredients (meaning they can drink milk, eat cheese and plain yogurt, but cannot eat ice cream since it is mixed with sugar).

All Eaters have silver eyes, and if a Siren Eater uses their ability, their eyes turn violet.

Eaters do not have clans.

Ater Zone

It is an area that has been contaminated by dark energy. Because of this, there is a high concentration dark energy and more demons spawn in this zone. Only B rank and higher spawn in it.

There are multiple Ater Zones all over the world, but the one that is very near to a city is the one near Seoul.

Dark Hours

The time between 11 pm and 12 am.

It is the time where monsters become considerably more powerful, and because of this they emit a faint red aura.

Institute of Mystic Defense (or more commonly named The Institute)

It is an organization that seeks to maintain the world’s current peace state. And also to prevent humans from ever knowing the existence of supernatural creatures.

While there is a variety type of people who work for the Institute, most of them are Eaters; and most Eaters work for the Institute. (This is because Eaters are peace loving people)

The ones that lead the Institute are the Council, and bellow them are the Ministers.
There will be one Minister for every country, and it is mandatory to report to the council every two months via reports.

The Minister in charge of S. Korea is Claire, and she also doubles as the Head of the Seoul District. However, since Korea is a relatively peaceful country, Claire doesn’t have much to worry about. And the other Eaters will report to Claire via reports every month.

Local Vampires and Werewolves usually help the Institute's members.

Aterwatch

Besides being a normal pocket watch, it is also used to detect if there is a demon or if a demon is going to spawn nearby. The map feature can be used to locate the demon/spawn area, and they can also show nearby Aterwatches.<