Birdman hails from Birdstar, a celestial body that maintains universal peace. Initially known as Superman, he later adopted the Birdman identity. As a galactic guardian, he recruits individuals—primarily children—from Earth and other worlds to become Permans, superheroes outfitted with specialized gear: a strength-enhancing helmet, a flight-capable cape, and a communication-enabled badge. Birdman enforces strict secrecy regarding their identities; violations originally led to brain cell destruction, later revised to transformation into an animal. He provides each Perman with a copy-robot duplicate to manage their civilian lives during missions.

Physically, Birdman appears as an average-build humanoid. His distinctive attire includes a black helmet with a beak-shaped front and golden wing adornments, a red cape secured by yellow shoulder pins, a gray bodysuit marked with a red "B" on the chest, black briefs worn externally, white gloves, and a white garter. He travels via a single-passenger UFO, occasionally demonstrating clumsiness in its operation.

As a mentor to the Permans, Birdman exhibits a direct and decisive approach. His recruitment methods involve unconventional tests, such as having candidates inflate balloons he then pops, as seen with Mitsuo Suwa. He strictly enforces discipline concerning secret identities but also shows understanding when Permans face emotional conflicts, like Sumire Hoshino revealing her identity to Mitsuo. His oversight extends galaxy-wide, selecting candidates across different worlds. He eventually chose Mitsuo as his successor for advanced training on Birdstar. This transition required Mitsuo to depart Earth with a promise to return, leaving his copy-robot behind. Birdman's legacy connects to broader narratives, as adult Sumire later references waiting for Mitsuo's return in related stories.