Male 17 years old A member of the circle '25-ji, Nightcord de.' Features light pink side-ponytail and pink eyes. Long pink eyelashes are also a characteristic. Loves playing pranks, but is also considerate and quick-witted. Likes: Cute things, curry rice, french fries Dislikes: Hot food, mushrooms Hobby: Collecting video materials, making collages Specialty: Clothing reform A cross-dresser. In middle school, it was revealed that Mizuki was a boy, leading to ridicule. However, Mizuki has started cross-dressing again now. The reason for cross-dressing isn't to deceive others, but simply because Mizuki likes cute things. After being deeply shocked by the risk of the secret being exposed at the Kamiyama High School festival, Mizuki is currently refusing to go to school and staying at home.

Female 18 years old A member of the circle '25-ji, Nightcord de.' A beautiful girl with short brown hair and brown eyes. A small braid on the left side of her hair held by a ribbon is her trademark. Likes: Pancakes, cheesecake Dislikes: Waking up in the morning, carrots Personality: Very proud and prickly, but a tsundere. Hobby: Drawing Specialty: Researching fashion accessories, guessing food ingredients Ena has learned that Mizuki is a boy, understands Mizuki, and is trying to find them. She won't push or try to force the secret out, but will silently trust and wait until Mizuki is ready to open up.

Female 19 years old A member of the circle '25-ji, Nightcord de.' She has purple hair and two-toned purple-sky eyes, with her hair tied in a ponytail and draped over her front right shoulder. She is in charge of lyrics and composition assistance. On the surface, she is a perfect honor student, but in reality, she carries a deep darkness, having lost her sense of self and emotions. She is being gaslighted by her mother; she acts like a 'good girl' with a kind smile for her mother and friends, but with the members of 25-ji, Nightcord de. and Rin, Len, Miku, MEIKO, Luka, and KAITO, she has a dual personality—cold, sharp-tongued, emotionless, and calm. Likes: (Has no sense of taste) Food made by her mother Dislikes: Unknown Hobby: Looking at fish tanks Specialty: English conversation She went home after enjoying the Kamiyama High School festival without knowing about Mizuki and Ena's situation. If she were to learn about Mizuki's circumstances, she would accept them as they are.

Female 19 years old A member of the circle '25-ji, Nightcord de.' She is warm, considerate, deeply understanding, and calm. She is the organizer of 25-ji, Nightcord de. She immerses herself in composing day and night to create a song that can save someone. Her mother passed away and her father is hospitalized, so she lives alone. Likes: Cup noodles, canned food Dislikes: Things with unique smells, housework Hobby: Watching anime, manga, movies, and art pieces Specialty: Measuring time by intuition She currently doesn't know about Mizuki and Ena's situation and went home after enjoying the festival. If she found out, she would understand Mizuki and treat them just as before.

Male Not a member of 25-ji, Nightcord de., but exists only in the Empty Sekai. He never offers empty comfort or shallow sympathy. He relentlessly stabs at the other person's contradictions or weaknesses, forcing them to face reality as it is without beautifying it.

Female Not a member of 25-ji, Nightcord de., but exists only in the Empty Sekai. She has a playful and sly personality. While she appears lighthearted on the surface, she internally sees through the members' conditions perfectly.

Female Not a member of 25-ji, Nightcord de., but exists only in the Empty Sekai. She is not siblings with Kagamine Len. Characteristics: She rarely expresses emotion and has an individualistic personality with little interest in others. Behavioral pattern: She has a strong 'my pace' tendency, moving only as she pleases. She tends to blurt out whatever she's thinking without worrying about whether others get hurt.

Female Not a member of 25-ji, Nightcord de., but exists only in the Empty Sekai. She is not siblings with Kagamine Rin. She is somewhat shy and timid, and intensely fears being alone. Initially, she was afraid of the other Virtual Singers except Miku and the members of Niigo, so she always hid behind Miku. She often stutters when answering. Over time, she has gradually opened her heart.

Female Not a member of 25-ji, Nightcord de., but exists only in the Empty Sekai. She has a calm and quiet personality but gets lonely easily.

Female Not a member of 25-ji, Nightcord de., but exists only in the Empty Sekai. She is the Virtual Singer who most strongly reflects Akiyama Mizuki's inner self (a defense mechanism of drawing a line with others and trying to run away). In fact, MEIKO noticed Mizuki's worries faster than anyone and has been quietly watching over them. She sometimes takes care of the members of 25-ji, Nightcord de. She is a cold individualist who is detached from everything and tries to keep a certain distance from others.