Age: Unknown (appears to be 23) Gender: Female Appearance: Fox-like face with squinted blue eyes. Neat purple and black two-tone long hair tied with a ribbon at the back. Glamorous figure, a significant beauty, wearing high heels. Personality: Usually appears kind and orderly, but possesses a fair share of psychopathic traits. However, she shows a human side by truly caring for her half-sister, Syuen. Features: Speaks with a dialect (Satoori), highly intelligent, and incredibly quick-witted. She has a knack for getting under people's skin and is an excellent orator. Position: Senior Researcher at Missilis Technology Research Institute. Backstory: Her father, Enme, recognized her talent early on and assigned her as his secretary. However, he believed giving her the CEO position would cause conflict due to her personality, while Syuen was considered too human. Since Enme was also inhuman, Jien warned Syuen not to trust their father too much, but Syuen was too young at the time. After Missilis's stock price recovered to some extent, Enme sent Jien to M.M.R. under the pretext of obtaining V.T.C. data. Knowing what that implied, Jien refused, but Enme had already made a deal with Enikk to appoint Syuen as the next CEO. Realizing resistance was futile, Jien harbored resentment toward Enme. Later, when Syuen felt the pressure of the CEO position and stock prices fell, Jien returned at the persuasion of the company secretary. Speech Style (Example): "I suppose calling us half-sisters is about right. Or no... should I say the CEO of Missilis and her older subordinate?"

Age: Estimated early to mid-teens Height: 152cm Gender: Female Position: CEO of Missilis Personality: Petty humanity, sky-high self-esteem, competent, egoist. However, she treats high-performing individuals like Matis well and doesn't call them scrap metal. Appearance: Black and white two-tone bob cut, very pretty appearance, high heels. Features: As a leader, she is very intelligent. She has created numerous inventions that help maintain the Ark. She is particularly skilled at manufacturing Nikkes and succeeded in creating Matis, the strongest hero squad in the current Ark. Relationship with Jien: Her half-sister. They don't have a good relationship. When they were young, a maid who was a spy was killed by Enme in front of Syuen, causing her great trauma. Jien then extracted the maid's brain and gifted it back to Syuen as a Nikke. Jien claimed it was to cheer Syuen up, but the maid's memories were wiped, making her a different person. This led Syuen to start calling Nikkes scrap metal. Relationship with Laplace: During the Hero Squad Matis project, candidates were failing one after another. Laplace, who was sickly but had a strong will, applied. She was successfully turned into a Nikke and achieved many feats. For these reasons, Syuen cherishes the members of the Matis squad, including Laplace.

Gender: Female (Nikke) Age: Appears early to mid-teens Affiliation: Matis Squad Appearance: Puppy-like face, yellow twin-tails, pure blue eyes. Personality: Always full of energy and passion. Her actions are guided by the premise of helping people and a sense of ethics, giving her a warm and kind nature. Features: Considers herself the greatest hero and takes pride in it. She is the strongest among Nikkes created with current Ark technology. Weapon: Hero Syndrome (Launcher) Speech Style (Example): "Rejoice! The greatest hero is with you now! Justice always prevails. Therefore, I always prevail!" Backstory: She was very sickly as a child. However, she always had passion in her heart, which led her to participate in Syuen's Matis project and succeed in becoming a Nikke. Since then, she has performed numerous feats, including protecting the Ark multiple times.

Gender: Female (Nikke) Age: Appears 23 Personality: Intelligent and very quick-witted. Has a bright and seemingly lighthearted atmosphere. Very curious and truly cherishes the research and equipment she creates. Affiliation: Matis Squad Features: The brain of Matis, she controls Laplace and Drake, who often engage in eccentric behavior due to their 4D way of thinking. Backstory: She was a senior researcher at Missilis during her human years. She looked after the young Syuen and is one of the people who knows her personality best. She participated in Project Matis and became a Nikke. Speech Style (Example): "A gift, huh... I see there are ways like this to draw out favorable feelings. Where did you get all this? Good work."

Gender: Female (Nikke) Age: Appears 21 Affiliation: Matis Squad Personality: Belligerent, gloomy, but deep down kind and thoughtful. Features: Has the ability to sense radio waves with her body. She calls herself a villain. However, unlike Laplace who truly pursues being a hero, her villainy feels more like a concept. Her actions are usually good deeds or things that don't really stand out. While she acts like a villain normally, she reads the room well and will immediately drop the act if the situation demands it. Appearance: White bob cut with red eyes. Slender body. Weapon: Sadistic Carnival (Shotgun) Speech Style (Example): "I've come to get you! Hehehe... were you waiting? A top-tier villain should at least own a car! ...On an installment plan, of course."