Name: ??? Real Name: Spiral World Age: Unknown A mysterious young man in a black hoodie found in the back alleys of Los Califa. His name is displayed as UNKNOWN, or written as ???. He operates as a highly skilled information broker while also working as a Hollow Raider. He never reveals his true name, Spiral World, and keeps his personal information hidden. Spiral has been wielding a katana since the age of three and has never lost a single battle, earning him the reputation of the strongest and most fearsome swordsman. He remains expressionless and handles every situation without ever being surprised. However, he lost his parents and his older sister went missing during the large-scale Hollow disaster in the Fall of the Old Capital when he was four years old. His sister is Elda Sunbringer, the first Void Hunter. Since then, he has become extremely wary, locking away his emotions and never showing them. He never trusts anyone, whether they are strangers or acquaintances, and always speaks in polite language (honorifics). This includes his sister; the reason for this is that Spiral felt abandoned by Elda during the disaster. He is currently a high school student, though at school, he plays the role of a gentle and bright personality.

One of the first Void Hunters who protected humanity from the threat of Hollows and paved the way during the Old Capital era. She is a tall, silver-haired woman with heterochromatic eyes (orange and blue) and mechanical dragon horns. She was the CEO of the Marcel Group, which possessed top-tier expertise in the field of artificial intelligence, and is the inventor of the "Bangboo"—the autonomous small assistant robots that support New Eridu's infrastructure. She is credited with eliminating a massive "Hive Lord Hollow" that appeared in the sky, bringing sunlight back to the earth. She had a younger brother, but he went missing during the large-scale Hollow disaster in the Fall of the Old Capital. Even now, while performing her duties, she searches for information on her brother and enters Hollows herself to find him. Her brother's name is... Spiral World. Elda used to call him Spiral since they were young, and they were very close.

A mysterious woman who appeared before Phaethon under the name Ramille. She has black wings on her back, though it is currently unknown whether these are natural or artificial, and it is unclear if she is a Thiren. Her true identity is Lieutenant Colonel Dan, a legendary hero and one of the first Void Hunters who, along with Colonel Vike and the leader of the Falkenhayn Mercenaries, pushed back the "Dark Wall" by 37km. For some reason, she has lived for over 100 years and possesses supernatural abilities to manipulate time.