Peganosuke, a pegasus, exhibits a timid nature and struggles with self-confidence, traits uncommon among his kind. He earns his living as a package-delivery courier. As the twin brother of Yunihiko—a mischievous unicorn who relishes manipulating others—Peganosuke presents a quiet and shy contrast to his sibling.

Physically, he possesses purple hair and sky-blue eyes devoid of visible pupils. He quickly befriends Uruno, the central wolf character, bonding over their shared feelings of inadequacy and mutual lack of self-assurance. When Uruno urges him to engage more boldly with life, Peganosuke responds by using his flight ability to carry Uruno on aerial journeys. These shared experiences reveal new perspectives and unseen sights, helping Peganosuke gradually find joy and value in his own capabilities as he moves toward self-acceptance.

Within their forest community of misfit animals, Peganosuke interacts with fellow residents who defy species expectations, such as a non-swimming orca and a near-sighted eagle. Fukurou, an owl known for her blunt speech, secretly harbors a crush on him, adding complexity to the group's dynamics.