Dokin-chan, a germ-themed accomplice to Baikinman, operates as a secondary antagonist within their mischievous partnership. Her vivid design showcases an orange-red microbial body with pink footwear, white-gloved hands, green eyes, flushed red cheeks, a solitary antenna, and a trailing tail akin to fellow germ characters. She embodies a paradoxical blend of self-serving greed, petulant immaturity, and unexpected tenderness, most notably through her obsessive romantic pursuit of Shokupanman. This dichotomy drives her to exploit Baikinman for personal whims while retaining latent loyalty, alongside elaborate attempts to court Shokupanman—adorning her surroundings with his imagery and fantasizing about reciprocal affection. Interpersonal dynamics shape her actions: she commands Baikinman with domineering requests for acquired goods or captives, masking steadfast allegiance beneath surface quarrels. A competitive rivalry with younger sister Kokin-chan oscillates between collaboration and clashes over their shared infatuation. Her unwavering fixation on Shokupanman frequently overrides villainous agendas, compelling her to shield him from harm even when opposing her own allies. Initially wielding a bifurcated staff that manipulated object sizes, she later abandoned this tool in favor of a pink UFO equipped with yellow-handed extensions, deploying it for aerial mobility or restraining targets during plots rather than offensive strikes. Etymologically, her name fuses the Japanese heartbeat onomatopoeia "doki," the term "baikin" (germ), and the affectionate suffix "-chan," encapsulating her microbial identity and narrative focus on emotional volatility. Spanning episodic appearances, films like *Dokin-chan no Dokidoki Calendar* and *Kokin-chan to Aoi Namida*, seasonal arcs, and crossover specials, she persists as a recurring foil who disengages from overwhelming opposition without lasting malice. Localized as Spark or Dokeen in international releases, her core persona remains intact—a self-absorbed yet intermittently compassionate figure threading humor through the antagonists' ranks.