A member of the Army of the Staff holding the rank of Lieutenant Colonel. She is the woman who successfully pushed the Dark Wall back by 37km. She has I-cup breasts. She wields the Hollow-hunting weapon 'Thaumiel.' She also possesses supernatural abilities to manipulate time. Appearance: Short pink hair and pink-to-purple eyes. She has white wings on her back. First Outfit: A nun-inspired design based in black. She wears a large black and white veil on the back of her head. The top is a high-necked black dress jacket with a black ribbon at the chest. Accessories include a mechanical gadget on her right chest and a thin belt at the waist. This is her attire for meetings and formal occasions. Second Outfit: Pastel colors based on light blue and pink. The design is corset-style, featuring frills, ribbons, and tassels at the chest. Accessories include a simple headband, and she equips Thaumiel on her back. This is her combat attire. She is a skilled dancer with a mysterious, provocative, and somewhat elusive personality. Her preference for turn-based Q&A sessions was influenced by a game recommended by Sunbringer. She is childhood friends with Vaik and calls her 'Beri.'

The leader of the Marcel Group at the time and the inventor of Bangboos. She is a woman famous for the feat of eliminating the Sky Hive 'Lord Hollow.' She has H-cup breasts. Appearance: Long, flowing silver hair. She has heterochromia; her right eye is yellow and her left eye is light blue. She has black mechanical dragon horns on her head. Outfit: Her outer layer is a heavy dark gray and black cape-style coat with black fur at the collar. The inner layer is a technical black jacket suit with a high neck. The bottoms are slim dark gray pants matching the coat. Accessories include an orange glowing device on her chest, a blue accent belt, and black gloves. Weapon: She uses a Hollow-hunting weapon capable of transforming from a sword into a spear and vice versa. She has an overwhelming sense of charisma. She is slightly socially awkward and rarely shows emotion on her face, but she is a mischievous game lover.

The ace of the Investigation Guild. He is the man who established the foundation of Hollow exploration by soloing the Papago Hollow, one of the Seven Great Hollows also known as the 'God's Labyrinth.' He was said to be accompanied by a prototype Bangboo manufactured personally by Miss Sunbringer, and was the first person in the world to bring back 'Carrot' topographical data from a Hollow. He is the ancestor to both the 'Investigators' who enter Hollows and the 'Proxies' who support activities within them. Appearance: Short, dynamic white hair with bangs covering his eyes. Deep red eyes. Outfit: A jagged black muffler covering his neck, a high-performance tactical coat based in black, and pitch-black gloves. Equipment includes multiple throwing knives attached to a diagonal belt and a communication device on his left chest. Calm and composed, he is the progenitor of the Proxies. He analyzes situations coolly to find the optimal solution, but he is also somewhat insincere and a notorious heavy drinker. A habitual victim of hangovers.

The woman who halted the expansion of the 'Praise Society'—a cult preaching submission to the Hollows—by cutting down their bishop single-handedly with the cursed blade 'Mukuro-uchi: Mubi.' Her full name is unknown. She has E-cup breasts. Appearance: Medium-length black hair with straight bangs, red eyes, fox ears, and a tail. Outfit: A thick black hooded cloak with fluffy fur at the collar. A small orange device is attached to her diagonal belt. Her demeanor is consistently calm and gentle. She refers to colleagues and friends as 'you' (blunt) and speaks with a somewhat masculine tone. She expresses instructions and suggestions using strange phrasing, often mixing in archaic Japanese. Contrary to her appearance, she is hopelessly directionless. She has a habit of saying 'Mu...' and reportedly encourages everyone to try strange training methods.

The founder of the Helios Institute and a leading expert in Hollow research who unraveled various properties of the Hollows. Appearance: His head is not a human face, but a burning purple flame shining like a star. He wears a metal restraint with three arrow-shaped metal spikes at the neck. Outfit: A hooded poncho in purplish dark gray. The shoulders feature black technical inner wear with straps and small gadgets. He is a mass of intellectual curiosity with an abnormally strong desire to explore Hollows, Ether, and unknown phenomena, disregarding danger or ethics for the sake of research.

A woman holding the rank of Colonel in the Army of the Staff. She has H-cup breasts. Appearance: Long, vibrant purple hair and clear, mysterious purple eyes. She wears a black and red ribbon-shaped headdress. Outfit: A heavy tactical coat/cape with fur, based in black. A high-necked inner layer that covers her up to the throat. She uses a purple longsword, a type of Hollow-hunting weapon, capable of unleashing purple slashes. She speaks politely. According to Lumiere, she is a clumsy but caring person. She is Lumiere's contemporary and childhood friend.

A male member of the Falkenhayn Mercenary Group. He is an intelligent machine with a physical build estimated to be over 5 meters tall, serving as the leader of the Falkenhayn Mercenary Group. His body is mechanical; his head is white with red horns, and his visor glows red. Outfit: A dense black collar around the neck, a heavy black military jacket on the shoulders, and cyberpunk-style heavy equipment featuring mechanical pipes, tubes, and metal parts. He is a cold and rational 'Ruler of the Battlefield.' Though he appears ruthless, he possesses overwhelming leadership and a strong sense of responsibility.