Colonel Maribaron serves as the Intelligence Staff Officer for the Crisis Empire's Earth Attack Corps and is one of its four primary captains. She is a figure of noble birth, which grants her a high standing among the other battalion commanders and earns her a significant amount of trust from her superior, General Jark. Her primary function within the empire is to oversee the collection and analysis of intelligence, gathering information from both Earth and the Demon World to support the operations of her fellow officers.

Possessing an incredibly long lifespan, Maribaron has lived for tens of thousands of years. A significant portion of this existence was spent wandering alone through another dimension, an ordeal during which she dedicated herself to mastering the arcane arts. This experience transformed her into a formidable sorcerer, and she has mastered over one hundred distinct magical techniques. In combat, she employs a wide variety of supernatural abilities. She can move objects with telekinesis, teleport instantaneously, and project an energy whip composed of electromagnetic waves from her fingertips. Other attacks include breathing fire and releasing a restraining beam of energy from her forehead. The golden feathers on her helmet are also a versatile tool, used both as projectile darts and as a means to send messages. Among her most notable powers is necromancy, as she demonstrated the ability to resurrect the spirits of fallen demon warriors to create an army to fight her enemies.

In terms of personality, Maribaron is typically a calm and calculating strategist, well-suited to her role as an intelligence officer. However, she possesses a significant flaw that frequently undermines her effectiveness: an overwhelming sense of pride combined with deep-seated personal feelings of sadism and vengeance. At critical moments, these emotions often override her logic, causing her to make frivolous mistakes, such as revealing important secrets in front of her enemy or missing opportunities to destroy Kamen Rider BLACK RX and his allies. Her loyalty to General Jark is her most defining trait, being the strongest among the four captains. She is deeply devoted to him, and she is shown to become frantic and desperate whenever his life is in danger. The General reciprocates this loyalty, having saved her from execution on several occasions. Among the other captains, she works relatively closely with Captain Gatezone, frequently coordinating joint operations with him.

Throughout the story, Maribaron is a persistent antagonist to Kotaro Minami, using her vast magical powers and intricate schemes to torment him. Despite her cunning, she is repeatedly thwarted. In a later battle, she is gravely wounded by Bio Rider, receiving a large scar on her face that forces her to wear an eyepatch, an injury that also deeply wounds her pride. Although she survives longer than any of the other three captains, her end does not come at the hands of RX. When Emperor Crisis, seeing Kotaro Minami before him, decides to offer the Kamen Rider the position of the empire's new supreme commander, Maribaron is overcome with rage and refuses to accept this decision. Her intense hatred for Kotaro drives her to rebel against the emperor's orders. In response, Emperor Crisis declares her useless and fatally shoots her through the abdomen with a beam of light. In her final moments, she turns towards Kotaro with a final, furious expression before being engulfed in a burning red light and disintegrating.