OVA
Description
Doppel is a member of the Monster Ops: Neutralization team, often referred to as MON, where she serves as the primary infiltrator. Her real name is a series of unpronounceable sounds from her native language, so she uses the alias Doppel, a reference to the doppelganger myth. Her true form is considered so eldritch and terrifying that she admits a human mind could not handle seeing it, and she maintains a more palatable default appearance to interact with the world. This default form is that of a petite young girl with tanned or dark skin, very long white or light-colored hair, and eyes with black sclera and yellow irises. In this form, she stands 129 centimeters tall, weighs 25 kilograms, and has a birthday of May 30th.

Doppel possesses an incredibly carefree, whimsical, and mischievous personality. She is a natural trickster who delights in pulling pranks on others, often pushing the boundaries of what is considered appropriate, but usually stays just within the line of acceptability. Her sense of humor is described as playful, and she loves to tease her colleagues and acquaintances, frequently making sharp or sarcastic comments. She has stated that she loves her job because she can do whatever she wants to anyone who has broken the law, indicating a slightly sadistic side to her enjoyment of punishing criminals. Despite her chaotic tendencies, she is not malevolent. She has a caring side for her friends, even if she does not show it openly, and she can become protective of her teammates, such as when she feels Manako is being threatened.

Doppel joined MON as a subordinate of Kuroko Smith, utilizing her unique talents for transformation and infiltration in special missions. Her role in the story is primarily as an operative for this special forces team, where she handles dangerous fieldwork in criminal investigations. She often impersonates hostages or suspects to lead criminals into traps or to lower their guards. Her motivations for working are less about justice and more about the personal enjoyment she derives from her work; she has confessed that using her powers against bad guys is fun. In her free time, she even takes it upon herself to hunt down individuals violating interspecies laws to prank and punish them for her own amusement.

Her key relationships are defined by her playful and often teasing nature. She is a loyal, if mischievous, member of the MON team, working closely with colleagues like Zombina, Manako, and Tionishia. With Zombina, she often plans pranks, though Zombina's impatience can cause their schemes to fail. She refers to the series' protagonist, Kimihito Kurusu, as boyfriend in a teasing manner, finding his earnest and serious attitude amusing. Doppel initially seemed frustrated by his indecisiveness and was the mastermind behind the Threat Letter D incident, a prank orchestrated to try to force him to choose a partner. Over time, she appears to warm up to him, showing hints of affection, though she is less open about her feelings for him compared to other MON members. She also has a close working relationship with her boss, Kuroko Smith, even helping Smith relieve stress by mimicking her form and personality.

Doppel has shown a degree of character development, primarily in her interactions with Kimihito. While she began as a distant prankster who caused him trouble out of frustration, she gradually becomes more involved in his life, even using him as bait for her pranks and eventually showing genuine, if subtle, signs of affection. Her relationship with her teammates has also deepened to a point where, despite her constant pranks, they trust her implicitly in the field, and she has been known to show a protective side towards them.

Her most notable ability is perfect shapeshifting. She can transform into any person, human or non-human, copying their appearance, voice, and mannerisms down to the smallest detail. Unlike the traditional doppelganger myth, meeting someone she is impersonating does not cause death. Her shapeshifting requires conscious effort; if she falls asleep or is knocked unconscious, she will revert to her default form. Additionally, her hair is extraordinarily versatile. She can stretch, morph, and control it as if it were an extra limb, and it is as strong as iron, allowing her to use it for defense. Her hair also serves as her clothing, transforming into the outfits of the people she mimics and shaping itself into furniture like chairs or hammocks in her default state. She possesses some hand-to-hand combat skills, having demonstrated the ability to kick an orc in the face with great flexibility. She is also a skilled actress, a necessary complement to her physical transformations to effectively manipulate and deceive her targets.
Cast