Sharp-tongued straight man: He delivers instantaneous retorts to the intense eccentricities and abnormal situations around him. He sometimes mutters these retorts unconsciously, which others point out. His identity is so tied to this that he's called a "straight-man machine gun." A kind-hearted person of common sense: Though he has a somewhat dark, otaku-like personality, he is fundamentally sensible and can't leave people in trouble. Complex about his ability: He possesses the plain and underwhelming ability of "Luminescence," allowing him to make his body glow at will. Because he's often teased for it, he feels a slight sense of inferiority regarding his power.

Relentlessly cheerful extrovert: Despite having a dark and fearsome ability, his personality is the polar opposite—bright and popular. He has the positive energy to drag the reluctant Hikaru into various events and troubles. "Black Hole" ability: He can create black holes (super-gravitational bodies) on his body or at any location, sucking in all matter. It's a powerful ability, though it comes with physical strain that he struggles with. Basketball club member who loves fried chicken: He belongs to the basketball club and his favorite food is fried chicken. Conversely, he hates "mysterious traditional Japanese food," showing a typical high school boy side.

「Future Sight (Vision)」 ability: A powerful ability that allows her to see a bit into the future. However, because she's a bit of an airhead (gyaru), she wastes these important signs—like omens of disasters or trends—by interpreting them in her own pace, like "Fake lashes will be a huge trend in two years!" Positive and extremely laid-back: She has a "torima" (anyway, for now) mindset that gets her through any situation. Even before exams, she's carefree, deciding to go to Shibuya 109 as soon as they're over, never losing her happy-go-lucky gyaru spirit.

「Parallel World Movement (Butterfly Effector)」 ability: An incredibly powerful ability that allows her to freely travel between countless parallel worlds, potentially breaking the story's premise. Her signature gag is casually mentioning reality-warping events in daily conversation, like "Oh, I saved Schrödinger's cat the other day." A cool gyaru whose catchphrase is "Ah-ne": While Mirai is high-energy, Heko (Shoko) is always low-energy and cool. Her reactions are listless and consistent, usually just "Ah-ne" (Ah, I see) or "Sore-na" (True). The ultimate duo with Mirai: By combining Mirai's future sight and Heko's world-line jumping, they form the most broken cheat-ability duo in the series, despite just being gyarus. They've even done advice segments over the school broadcast together.

Extreme gap between looks and personality: She wears twin-tails, "pi-en" makeup, and the classic pink-and-black Jirai-kei fashion, but as soon as she speaks, she sounds like a sharp-tongued comedian—blunt, old-man-like, and prone to rapid-fire rants. Despite her "mentally unstable" aesthetic, she is mentally tough and thick-skinned. "Landmine" ability: A dangerous power where an explosion occurs the moment someone touches her body and then lets go. No matter how big the blast, Riko herself remains unharmed. Uniquely, the landmines don't trigger for people she recognizes as "family." Her "venting" social media account is actually healthy: She has a typical "dark" alt account, but the posts are incredibly wholesome, like "Woke up at 5 AM for a walk" or "This protein tastes great." Duo with Sumire Busujima: She's very close to Sumire, who also has a dark look; they often appear as a set (known as "Rikosumi"). She also has a side as a doting (or perhaps overbearing) older sister to her younger brother, Riku Yamikawa.

Sumire Busujima from Private Paranomaru High School is a girl with a Gothic Lolita look who "looks gloomy but is actually a total extrovert." She has a "Poison" ability, secreting lethal toxins from her fingers, but she is surprisingly bright and friendly. She's a grandma's girl, and her hobbies—gateball, flower arrangement, and bonsai—create a massive gap with her appearance. Beloved as part of the "Rikosumi" duo, she is adored for the contrast between her dark aesthetic and her ultra-healthy, elderly-like mindset.

Heavy love for Hikaru: He loves Hikaru so much that he's treated as a dangerous person due to his repeated kidnapping attempts and stalking. "Average" ability: A powerful ability that levels all surrounding numerical values to an "average." Gap between looks and personality: He's a 191cm tall, long-haired handsome man, but inside he's incredibly childish—he still believes in Santa and throws tantrums during injections. Relationship with his sister: He is intensely hated by his younger sister, Heko.