Doppel

"Doppel" (real name unknown) is a member of the M.O.N., where she acts as the team's infiltrator. Despite claiming to be a Doppelganger, she is actually a Shapeshifter.

Appearance
Doppel's default form has the appearance of a small, petite young girl. Her skin is dark, she has very long light-colored hair and black sclera. However, this is not her real form. It's unkown what her real form looks like, but is implied to be very eldritch, being called a "faceless existence". Indeed, Doppel herself admitted that if humans were to see it, "their mind wouldn't be able to handle it".

Personality
Doppel seems to be a natural trickster, taking delight using her powers to prank people and loves seeing people freak out. It is said she often takes jokes too far. However, Doppel prefers to prank those who deserve it, such as criminals, as it is easier to avoid punishment that way.

She also seems to have a slightly sadistic side, and is not the most sympathetic of people; almost eagerly letting Smith attack the Orc Leader when she wanted to punish him. (Although, she did have some cause to be peeved with him.)

Physical Traits
As opposed to actual Doppelgangers, Doppel can become a perfect copy of a person without the person in question dying. It's possible her powers also allow her to change her scent, as she was capable of fooling Orcs into thinking she is human, despite Orcs having a very good sense of smell. However, Doppels requires a conscious effort to stay shapeshifted. So when she is unconscious, such as asleep, she'll revert back to her true form. In fact, even being half asleep causes her current form to become distorted, showing what might be part of her true self.
 * Shapeshifter Physiology:
 * Flexibility: Possibly a side effect of her shapeshifting, Doppel has shown to have very supple limbs, even in a transformed form. She was capable of lifting her leg up so high, she could kick an Orc much larger than herself in the face.
 * Prehensile Hair: Even when not transformed, Doppel can still control her hair as if they are limbs. She has used this ability to have her hair form a spiral chair to sit on. Her hair is said to be more useful than her arms or legs and is as strong as iron, so she can use it to defend herself.
 * Shapeshifting: As a Shapeshifter, Doppel's only known ability is shapeshifting. When she shapeshifts, her hair becomes the clothes her other form may wear. The full extent of her shapeshifting is still unknown, but she has been shown to transform into both humans, and various Liminals, such as Arachnes and Lamia.
 * Acting: When taking the form of another person Doppel not only has to take on their appearance, but their personality as well. She has become quite skilled at acting like other people, such as Smith. Her acting skills make her quite skilled at manipulation as well.
 * Self Defense Training: Doppel has demonstrated to possess some hand to hand combat skills. This, combined with her great suppleness, allowed her to knock an Orc down by kicking him in the face.

Skills and Statistics
Main: Doppel/Game Stats

Plot
She and her team were first seen when called in to deal with a gang of Orcs that had taken over a Libido Dojin where she disguised herself as a girl from one of the Dojin to draw the Orcs' attention. When the rest of the team showed up, she revealed her true form and attacked one of the Orcs. They later came to Kimihito's home with Smith for dinner.

Later when Kimihito caught a cold, Smith took time out from her heavy workload to "treat" him herself, leaving an angry and overworked M.O.N. to do all the work themselves. While Smith stated it was to keep the homestays away from the sick Kimihito to avoid a viral mutation, she simply wanted to slack off. However, when she caught his cold, her coworkers refused to help her for the same reason.

After the Director was webbed up by Rachnera and managed to call the police, M.O.N. were assigned to apprehend the Arachne (although Doppel was annoyed she didn't have anything to do), however she escaped. Later on they tracked her down to a warehouse where Sumisu agreed to having her transferred to Kurusu's household.

Later on, when Kimihito was sent a death threat. M.O.N. were assigned to act as guards while Sumisu went on a "date" with him, however the operation failed when Miia and the rest of the girls arrived.

During M.O.N's day off, she was asked by her teammates to participate in their plan to date Kimihito to lure out "D" but she gave the excuse of it "not being her scene". She instead secretly stalked them on their dates in disguise. She was found out at the end of Manako's date and was attacked by her team. Upon being hit by a tranquilizer dart from Manako's gun, she reverted back to her default mode, much to everyone's surprise. Later in the evening, as she was carried by Tio, she then confessed that she was the "D" who wrote the original threat. Doppel explains that she heard Smith complain that Kimihito kept getting more homestays while not being able to decide which one to marry. Doppel decided to write the letter to force Kimihito to get closer to one of them and asks if it worked. Zombina explains that the letter caused Kimihito to get closer to all of them, much to Doppel's dismay. When Zombina asks her why she didn't tell any of her partners, Doppel admits it was too much fun seeing M.O.N. work hard to find the culprit while not realizing it was her, with Zombina and Manako acknowledging that that's just the kind of person Doppel is. Doppel then confronts the three and forces them to admit they enjoyed their dates, which they all agree on. They then express their surprise at how Doppel was capable of writing the poetic second letter, only for a confused Doppel to reveal she only wrote one letter.

Zoological Classification
Shapeshifters are a race of beings that can take on any appearance they desire and are known as "shadow people". Although their true forms are unknown, they are said to be quite eldritch. It is believed they are related to a being called the "Faceless God".

Trivia

 * She named herself after the species she pretends to be: "Doppel" from Doppelganger. This is because her real name cannot be pronounced or understood by humans.
 * However, Doppel's species is in fact, not Doppelganger. Since if she really were a Doppelganger, if she were to impersonate a person, they would die upon meeting her. Her real species is simply known as "Shapeshifter" and are implied to be very eldritch in nature.
 * She calls herself "Doppelganger" because other beings are more familiar with them than with her own species.
 * It is later revealed that the form we see regularly is not her true form and therefore she doesn't bother being embarrassed. She does however makes sure her hair covers "that" part of her.
 * Doppel is said to have an aura of "creeping chaos" around her.
 * Befitting her true nature, Doppel is shown to like reading books of Lovecraftian horror.
 * She is the only member of the M.O.N. that doesn't wear a uniform... or any clothes for that matter. Probably due to the clothes will get in the way when she transforming, and that her powers can "create" any form of clothing for her. This is no longer the case as of chapter 40, as she is shown wearing clothes in her default form at the end of the chapter, and actually finds it more embarressing than being naked.
 * In her default form, at a 129cm (4'2") she is the shortest character introduced so far. She's also the lightest at 25kg, which is 55lbs in US customary.
 * It is revealed that she wrote the first letter as D.
 * The way her clothes (when transformed) are made from her own hair may be a reference to the video game Bayonetta.
 * Doppel's true eldritch nature, as well as it being described as a "faceless existence" and a "creeping chaos", heavily references the Cthulhu Mythos deity Nyarlathotep, who is known as both the "Faceless God" and the "Crawling Chaos".
 * MonMusu Anime Twitter account revealed that her Birthday is May 30th.