Mister Kaneari functions as a recurring antagonist for the Gold Group. He employs his immense fortune to design and deploy intricate traps, aiming to stop phantom thieves from stealing treasures he protects. Extreme overconfidence marks his approach to these schemes, yet they consistently misfire due to miscalculation or unintended self-sabotage.

His appearance features light coral pink hair, purple eyes, a long pointed nose, and a mole positioned above the right side of his mouth; he is often illustrated with sharp teeth. He dresses in a formal suit adorned with golden trim on the collar and golden buttons, complemented by red-purple cuffs featuring lavender lace. Matching red-purple trousers, white shoes with dark brown soles, and square golden-rimmed glasses complete his attire.

He habitually concludes his sentences with the word "indeed." A defining trait is his intense possessiveness and notable affection for his pink teddy bear, Kintaro-chan. A recurring comedic element involves Kintaro-chan's nose acting as a trigger for various devices or traps. Invariably, Mister Kaneari accidentally activates this trigger, resulting in catastrophic explosions that typically destroy the location housing the treasure.

By the events of episode 30, he marries his assistant, Kaneko, demonstrating genuine affection for her. He refers to her as "sassy-chan" and exhibits jealousy when external influences like Cupid's arrows affect her affections. This marriage updates his status from earlier bachelorhood descriptions. His antagonistic role persists throughout his appearances, consistently focusing on orchestrating complex, often lethal, security measures against phantom thieves, primarily targeting Joker and his associates.