Dr. Eyepatch is a blue-skinned humanoid defined by three constant features: an eyepatch over his right eye, a black cloak, and a robotic arm. The eyepatch exhibits a unique trait, undergoing a complete redesign in every episode, sometimes multiple times within one. He communicates exclusively via television broadcasts from an undisclosed location, never engaging physically with others.

As the head of King's Idea Laboratory, he develops inventions and gathers critical intelligence. He regularly broadcasts technological gadgets or vital mission support information directly to recipients. His duties also encompass hosting special events, such as the NG awards ceremony.

His relationship with the robotic maid Tetsuko involves ambiguity; some sources claim he created her, though this remains unconfirmed across all media. Regardless of her origin, he consistently treats her with contempt, insulting her capabilities and threatening replacement with newer models.

His broadcasts follow a distinct pattern: after delivering the main message, he briefly departs the screen only to reappear moments later for a final, often abrupt, closing remark before the transmission ends permanently. He expresses a personal preference for the food "Donbatch." No character development, expanded backstory, or significant narrative evolution occurs beyond these established traits and behaviors throughout all seasons and official media.