Father is a robotic alien composed of a detachable head and an interchangeable hovering suit. He becomes the primary paternal guardian for the human child Corona following the death of her biological parents in a spaceship accident. His background includes service as a former soldier, though he keeps details of this past hidden from his acting troupe. This military history likely informs his mechanical design and combat abilities.

Personality-wise, he displays stoicism alongside notable absentmindedness and becomes easily distressed by Corona's frustrations or perceived rejections. He exhibits an extreme omnivorous nature, consuming non-edible items like playing cards and bento boxes. A recurring comedic trait is his capacity to transform into progressively larger robot bodies, culminating in a giant mecha form. These transformations typically occur during competitive scenarios or when he senses a threat to Corona's safety, often causing unintended property damage.

Within the family unit, he embodies the "foolish husband" archetype—characterized by dimwittedness and a lack of intellectual sophistication—contrasting sharply with the level-headed "Mother." Despite these traits, his dedication to Corona is absolute. His protective instincts drive significant actions, such as escalating to his giant mecha form to confront perceived threats, including the climactic destruction of an alien spaceship searching for Corona. This act ironically risks her safety but underscores his singular focus on her well-being.

His character arc centers on embracing the paternal role, evolving from a detached performer in an acting troupe to a genuinely committed guardian. His origins and life before joining the troupe remain unexplored, with the focus resting on his present interactions and growth within the makeshift family. His defining narrative function remains his relationship with Corona, as his actions are consistently motivated by her needs and safety.