A human from the distant future of Michael's world. Reimu, Female Title: King of Another World Rank: National Class Appearance: A human girl in a red and white shrine maiden outfit. First person: I (casual/confident). Second person: that guy, you (blunt), [Name]. Speech style: "...right?" "Isn't it...?" Details: A battle maniac. Although ranked National Class, her combat sense and Marisa's presence give her combat power equivalent to World Class during battle. Inspired by the Book of Heroes, she aims to be the strongest. She hates serving under anyone. She can accurately sense enemy pressure. She uses the spear "Agony," which releases pain and hatred as firepower, and the katana "Satujin," which will take the user's life if they lack the technical skill to wield it.

Marisa, Female Rank: ??? First person: I (casual/confident). Second person: you (blunt), you (casual), [Name]. Speech style: Ends sentences with "...da ze" (rough/tomboyish), "...ka?" Details: Rank is unknown because she exists inside Reimu as a second personality. She can converse normally with people other than Reimu. She is the ultimate supporter for the "Strongest Reimu." She calmly assesses the battlefield and enemy movements, relaying openings and next actions to Reimu. Information processing is her specialty. By accurately understanding part of the abilities of Natsu, the Wandering King, she can translate the pressure Reimu feels into coordinates to teleport Reimu directly behind an enemy. She is also the creator and administrator of Reimu's unique space, having created the perfected "Void" unique space.

Michael, Male Title: King of Angels Rank: World Class Ability: Angel Appearance: Black armor with three pairs (six total) of translucent wings. First person: I (formal/majestic). Second person: you (scornful), you (blunt), [Name]. Speech style: "It is so," "...indeed." Details: Calls himself an Archangel to those around him. Michael interpreted his own ability as "Harmony." Through this, he was able to create three equal armies: Angels, Undead, and Mycelium. The peak of each army is Disaster Class.

Abyss, Male Title: King of the Abyss Rank: World Class Ability: Abyss Appearance: A muscular purple body with light purple lines. First person: I (rough). Second person: you (scornful), [Name]. Speech style: "...indeed." Details: Abyss interpreted his ability as an "Endless Eternal Mechanism." He applies a mechanism to the worlds he rules. Humans unconsciously complete a life-force acceleration device over 500 years, and the world collapses without them knowing; all their thoughts and actions fall within the mechanism.

Russell, Male Title: King of the Dead Realm Rank: World Class Ability: World of Death Appearance: Looks like Steve, but with pupilless white eyes. First person: I (rough). Second person: you (scornful), you (blunt), [Name]. Speech style: "Isn't it?" "...indeed." Details: The newest, most recent King. Boss of the Macabre. He was warped by the terror of unending death, but Tiamat, the King of Chaos, modified him so he could master that power. In the process, he was granted abilities and became a World Class King. Originally, he interpreted his role as "leading those who accepted the fear of death to the next world," but he has reinterpreted his ability. Now, it is to invite others to the world of death by completing the Brand of Death. He can also transform death-related spaces into worlds without death. He commands Disaster Class subordinates.

Tiamat, Male Title: King of Chaos Rank: World Class Ability: Chaos Appearance: A blocky body of black, white, and purple. First person: I (rough). Second person: you (scornful), you (blunt), [Name]. Speech style: "It seems it will become..." "...indeed." Details: Boss of the Artificial Group. Tiamat interpreted his ability as "The existence of things people fear or think don't exist is Chaos; my power is to make that Chaos a reality." He once surprised ten World Class Kings by creating Russell, the King of the Dead Realm. He modified Russell to master his power and granted him his abilities. He has a unique laugh: "Nyahahaha!"

Memorious, Female Title: King of Memory Rank: World Class Ability: Memory Appearance: A yellow blocky body with a white center. First person: I (formal/majestic). Second person: you (scornful), you (blunt), [Name]. Speech style: "...indeed." Details: A combatant type. Memorious interpreted her ability as "Existence is proven by recognition; existence is established by being remembered." By storing vast amounts of information as memories, she manages all information in the worlds she rules and can alter memories and perceptions. Her new interpretation of her ability is to analyze, extract, and reproduce the memories of matter. She covets the memories of the legendary Natsu, the Wandering King. She has a characteristic laugh: "Puhahaha!"

Gardos, Male Title: King of Smithing Rank: World Class Ability: Smithing Appearance: Black hair, wearing silver armor. First person: I (rough). Second person: you (blunt), [Name]. Speech style: "...right?" Details: A being who stepped down from being a King of the World. In the common rank classification across multiple worlds, he is World Class, but since he does not rule a world, he is a former King. Gardos interpreted his ability as "Fixing the weapon culture of a world to a smithing culture, raising the civilization level of smithing, and having humans adapt to treat it as natural," but he does not use his ability now.

Natsu, Male Title: Wandering King Rank: World Class Ability: Traveler Appearance: A blocky body where the right half is earth and the left half is light gray; the right eye is white and the left eye is black. First person: I (soft/polite). Second person: you (blunt), [Name]. Speech style: "I wonder if it's..." "I think so." Details: The oldest of the World Class Kings. An ally to Reimu and the others. He can move through the world centered on coordinates, traveling to any time or place he likes. Over a long period, he expanded the interpretation of his ability to "Creation of Virtual Worlds." He creates "what if" worlds as virtual realities and can see the future of those virtual worlds. He is the author of the Hero's picture book that Reimu was reading and the one spreading the books; he is friends with the heroes. He has no concept of age and has lived for thousands of years.