Dr. Eyepatch is a blue-skinned humanoid distinguished by a signature eyepatch, a black cloak, and a robotic arm. He manifests solely through television screens, avoiding direct physical interaction. As the head of the King's Idea Laboratory, he oversees the creation of numerous inventions and technologies utilized in the series. His core function involves delivering new gadgets or essential information to the protagonist, Milk, specifically tailored to resolve each episode's central conflict.

A visually defining feature is his eyepatch, which exhibits a unique design in every episode and occasionally alters multiple times within one installment, reinforcing his enigmatic persona. He previously hosted the NG awards, cementing his role as a key informational source.

His connection to Tetsuko, an obsolete robot, remains undefined; some indications point to his potential involvement in her creation at the laboratory, though this is unconfirmed. Regardless, he consistently disparages Tetsuko and repeatedly proposes replacing her, establishing a dismissive or antagonistic dynamic. His influence potentially extends significantly beyond the laboratory, suggesting unacknowledged control over the show's world.

His background, origins, and character development remain unexplored across all official media, including seasons and related productions. His role, appearance, and interactions remain static, showing no depicted evolution or expanded narrative in any spin-offs or formats.