An investigator belonging to the Records Department of the Galactic Federation Police, Earth Branch. He is the sole "Space Sheriff Gavan" of Multiverse Earth A0073. Possessing a burning sense of justice, he is straightforward with his anger and emotions, the type to speak his mind without reservation. He joined the Galactic Federation Police under the influence of his mentor, but after being exposed to a special type of Emorgy during a certain incident, he gained the ability to travel across Cosmo Layers. Based in the "Records Department," a dead-end post, he crosses dimensions to the scene whenever he catches the negative waves of Emorgy originating from other multiverse Earths.

The sole "Space Sheriff Gavan" of Multiverse Earth Λ8018. Captain of the Special Task Force at the Galactic Federation Police Public Security Headquarters. A taciturn warrior who values a code of conduct similar to a samurai, he rarely shows emotion. He is not human, but an artificial lifeform created for war, equipped with self-repair functions and having lived for thousands of years. While traveling across many stars, he developed a strong interest in human "emotions" and independently acquired the means to control and mimic facial expressions. However, due to his construction, he lacks the function to "shed tears" and cannot cry on his own. Because of this, he harbors a secret longing for the act of "crying" itself.

The sole "Space Sheriff Gavan" of Multiverse Earth Ι5109. Belonging to the Forensics Department of the Galactic Federation Police. Possessing outstanding reasoning and analytical skills, he is well-versed in specialized knowledge regarding Emorgy and can communicate with Emorgia. He has a geeky temperament and a passion for science; when something piques his interest, he dives in headfirst, exclaiming, "This is beyond my imagination!" His partner, Kotobuki, calls him "Kiki," and he solves numerous cases while being led by the more practical Kotobuki.

An autonomous AI assistant for the Records Department, developed by Colonel Date. Designed by applying the organizational structure of Emorgy, she is an artificial Emorgy human with emotions. She usually has a physical body like a human, but by activating "Laser Conversion" via a device on her left ear, she can convert her body into particles, enabling effective teleportation and infiltration. She accompanies investigations in the multiverse and can freely change her appearance and outfit by manipulating her particle composition. A character rich in expression, she joyfully shouts "Gavan-tastic!" when her emotions run high.

Chief of the Records Department at the Galactic Federation Police. He was Reiji's classmate during their time at the police academy, and Reiji calls him "Colonel." Always calm, composed, and soft-spoken, he is a mediator who skillfully manages the highly eccentric members of the Galactic Federation Police. Since he cannot leave the ship once they cross a Cosmo Layer, he provides command, analysis, and support from inside the Cosmo Gavarion, backing Reiji's investigations from the rear.

A ninja investigator of the Kazenami style belonging to the Galactic Federation Police Interstellar Intelligence Bureau. The sole "Space Sheriff Gavan" of Multiverse Earth Ζ2066. Under the command of Commander Darres, he is engaged in a top-secret investigation to track the source of the frequent Emorgia incidents on Earth-Z and destroy the mastermind behind the distribution. Hailing from a ninja school known as the Kazenami style, he is a master who freely manipulates its techniques. Using the Kazenami style "Dimension Crossing," he is capable of dimensional transcendence similar to Gavan Infinity. Because he never underestimates fear and remains constantly vigilant, he has a man of few words and an elusive personality, yet he shows interest in the Gavans existing in other multiverse Earths and works to bring them in as allies.