Parasyte

Team Grey: An organization formed by the government specialized in taking out these parasites, they use special power guns. They may not have many information about the parasites yet. They use an x-ray scanner to scan a person to see if they are a parasite. If they are, the scanner would mark the infected spot red. However, mutants aren't spotted by this device, since they are part human and part parasite.

They have another thing on how to tell if someone is a parasite or not. Pluck out a piece of their hair and see if it curls in on itself or withers, because if it does, the person is a parasite. And yet again, mutants can't be found like this.

There's another thing they do. They have captured a person with a parasite, strapped it to a chair and kept a metal piece of device around it's head. The device would trigger when the parasite tries to do anything to escape, it will release smoke or gas that'll keep the parasite still. They would bring the parasite along with them in a black truck, and they taught the parasite to press a button given to it whenever it felt it's kin nearby.

Parasites are unknown beings that came from a shattered asteroid, going into a person's mouth or ear to infiltrate the brain and take over the body, was their their first goal, and their second goal is to kill and sometimes even switch bodies with another person by exiting the human they first controlled and into another. These parasites can have full control of the body once it has eaten the brain, controlling the human body. Although, these parasites don't know emotion, so the humans they control can't express any emotions easily.

The infected human's head can split into many different parts, often two, rarely four or five. Only the head can do that, the skin of the head can be used as blades or to fly. These things can't multiply. The parasites can be distracted or weakened by smoke, alcohol, or hand sanitizer once it's applied to its splitted head. These things can only die when they are striked or shot in the heart or to another parasite's strike.

The parasites originally landed in South Korea, possibly spreading or is already in other parts of the world. So, the setting will be South Korea. These parasites can sense each other by hearing a light ringing noise in their head when they're near their kin.

Although, when they enter a person near death or have a fatal injury, they have no choice but to heal the body's injuries before hijacking the brain, high rate of failing to take control, resulting in a mutant. A mutant is when a parasite and a human is one, where the parasite can only control the body for 3 minutes minimum to 2 hours max until the body tires out. The human also has a conscious, but can't communicate with the parasite in them through thoughts. The human won't remember what happened when the parasite takes control. The look of a mutant is that their face stretches, and only half of their face, not splitting into two or four.

The relationship between Mutants and Parasites aren't neutral nor close, instead, Parasites sees Mutants a being that is to be destroyed, since Mutants has learned to coexist with a human. Though, Parasites can't really tell a Mutant at first, only when the Mutant shows itself like stretching the face.

Parasites can fight each other, but they mostly work together because it's in their nature, they have no choice but to follow:

1. Escape From Egg.
2. Find A Human Host.
3. Hijack The Brain.
4. Take Full Control Of The Body.
5. Work With Other Parasites To End Humanity.

Though the reason for their goal to end humanity is unknown.

Parasites can't reproduce like humans or animals, so they are really determined not to be struck in the heart. When a Parasite dies with it's host, both turn into an ash grey before withering to ashes. A newborn parasite can't live without a host longer than half an hour, while a parasite that had escaped from it's host's body can live up to 50 minutes max.

What a newborn parasite looks like is like a fleshy shrimp without legs and only a pointy tip for a head, used to burrow into a host, looks like a worm with a horn. While an 'aged' or experienced parasite is as big as a lobster, fleshy like always, but the flesh can stretch and form a blade, they can switch hosts if they managed to get out of their original host.