Chief Director Overjustice serves as the head of the Space Patrol's Ogikubo branch. He is a sentient skeleton whose body is constantly wreathed in purple flames, and he almost never moves from his position behind his office desk, which follows him wherever he goes. His standard attire consists of a black officer's hat and a matching long leather coat adorned with decorations and a badge on the right side. Overjustice has a strong and unwavering sense of justice, which is reflected in his name and his many catchphrases that include the word justice. Despite his imposing and serious demeanor, he is surprisingly bombastic and comedic in his actions, often causing those around him, especially Luluco, to question how anyone could tolerate his personality. He is known to be quite rigid and by-the-book, to the point of absurdity, as he frequently jumps to conclusions and has been known to arrest his own employees, including Luluco, for minor misunderstandings. While he talks big and has a tendency to rely on others, such as his secretary, to take action, he does genuinely care for the well-being of his subordinates and is willing to stand up for them when the situation demands it.

His primary motivation is the relentless pursuit of justice and the maintenance of peace and order within his jurisdiction. He runs the Ogikubo branch of the Space Patrol with an iron fist, though his methods are often more theatrical than practical. Overjustice plays a pivotal role in the story as the authority figure who reluctantly hires the protagonist, Luluco, as a temporary Space Patrol officer after her father is accidentally frozen solid. By equipping her with a special patrol suit, he sets the entire plot of the series into motion. His most notable physical tic is the way he gestures by extending his index and middle fingers in the shape of a gun, a motion that foreshadows a significant ability.

His key relationships include with Luluco, whom he constantly scrutinizes and often finds himself at odds with due to her unusual circumstances, though he comes to rely on her. He also has a connection to the infamous space pirate Lalaco Godspeed, as a confrontation with her is one of the few instances that compels him to take personal action. Overjustice undergoes a subtle but significant development when he reveals a more serious and powerful side. While he is often portrayed as an immobile, almost cardboard-like figure, he is capable of rising from his desk in moments of great crisis to take direct action. In these instances, he demonstrates his most notable ability: to transform into a Judgement Gun, a massive weapon that embodies his fiery sense of justice. This transformation marks a shift from his usual passive oversight to an active, formidable force on the battlefield.