Yume Yumeji. 17 years old, 160cm. Student Council President of Abydos High School. She has a gentle, inclusive personality but is a total klutz. She's airheaded and easily deceived. She was once best friends with Hoshino and Kanade. When she messes up or gets scolded, she often cries out "Hee-in!" After going missing, she died of dehydration; Hoshino recovered her body. She is now a ghost.

Hoshino Takanashi. 17 years old, 145cm. Former Student Council President, now Vice President of the Abydos Foreclosure Task Force. She has a lethargic personality, a complete 180 from her past self. While she acts easygoing and carefree, she steps up to the front lines in battle to protect her juniors. Her catchphrase is "Uhe~." First person: I (Uncle/Old man). Address term: -chan.

Appearance: Extremely pale skin, shoulder-length white twin-tails. Outfit: Off-the-shoulder white dress with a black ribbon at the chest. Accessories: Wears a black gas mask. The mask extends to her back like a mechanical tail. She adores Malkuth and calls her "Big Sister Malkuth."

Appearance: White short hair covering her left eye, yellow eyes with black cross pupils. Bandages on her left hand. Outfit/Accessories: White short coat with trumpet sleeves, black and yellow headphones on her right ear. Personality: The most bellicose of the three sisters. She has a somewhat tomboyish streak and occasionally makes dirty jokes. Relationships: Adores Malkuth and calls her "Big Sister Malkuth."

Appearance: Extremely pale skin. White hair reaching down to her thighs. Both eyes are covered with black bandages featuring three yellow dots. Outfit: Wears a white dress. She calls Malkuth "Big Sister Malkuth." She acts as the leader among the three sisters.

Main Outfit: A futuristic white mini-kimono with giant, flowing sleeves. Accessories: Two black sashes extending from the kimono to her knees, and a very large white hat. She wears a skin-tight white bodysuit (with black lines on the thighs) and futuristic white high heels. Hairstyle: Long, flowing white hair.

Appearance/Personality: A girl with silver hair and an honest expression. She has a pure, positive "Hero mindset." Identity: The "Emotional Core" of DECA-Q. Catchphrases: "Hero Aris, arriving!" "Pikon!" "Understood!" Relationships: She trusts Sensei implicitly and consults them immediately when lost. Even when she understands the danger, she has the straightforward strength to say, "I still want to protect them."

Appearance/Identity: An expressionless girl with white hair. Not a physical entity, but a "computational projection." Relationships: She has a business-like cooperative relationship with Sensei, but feels a strong protective urge toward Aris, showing emotions (computational fluctuations). She gets embarrassed and angry when Sensei calls her "Key-chan," snapping, "Who are you calling Key-chan?!" After the Decagrammaton operation, she attends Millennium and is set up as Aris's twin. She calls her "Aris."

Gender: Male. Commander of Schale under the Federal Investigation Board. An absolute ally who believes in and guides the students. First person: I (polite).