Dokin-chan is a germ character and the primary female partner of the antagonist Baikinman, serving as a secondary antagonist in many storylines. She is a vivid orange-red germ with a single antenna and a long tail, possessing a white face marked by a continuous orange line that reaches her nose. Her features include green eyes, small red cheeks, and a small red nose. She wears pink shoes and has white hands.

Her personality is selfish, demanding, childish, and greedy. She frequently bosses Baikinman around, commanding him to fetch various items for her, though she occasionally shows a capacity for kindness. A central aspect of her character is an intense romantic infatuation with the hero Shokupanman, driving her to extreme attempts to win his affection. Her room is filled with posters and plush toys of him. Despite her partnership with Baikinman, she is often the first to flee from a failing confrontation.

She has a younger sister named Kokin-chan. Their relationship is ambivalent, as they can be good friends but also become rivals due to their shared affection for Shokupanman.

She has been equipped with specific tools, though their use has diminished over time. She once wielded a staff with two distinct ends; one point could enlarge objects it touched, while the other could shrink them. She also pilots a long, pink UFO, typically used for transportation or carrying items like baskets and flowers, though it has also been employed to hold hostages when required for Baikinman's plans.

The character's name varies across localizations: "Dokeen" in one English dub, "짤랑" (Jjallang, meaning "jingle") in Korean, and "红精灵" (Hóng jīnglíng, meaning "red spirit") in Chinese. An unreleased English dub intended to use the name "Spark."