Ammonia Pine is a former cleaning lady who worked at a research lab. One day she accidentally inhaled the fumes of an experimental bathroom disinfectant. The fumes had a strange effect on her and turned her into a cleaning-obsessed villain. She was later recruited by F.O.W.L. for their dastardly plans. She hates and is even afraid of dirt. She has a sister named Ample Grime, also a F.O.W.L. agent.
Ammonia Pine appears as the primary villain in only one episode, "Dirty Money" (the 3rd episode in production order). Her other two appearances - "Cleanliness is Next to Badliness" and "Dirtysomething" feature her paired with Steelbeak and Ample Grime respectively. She also makes cameo appearances in "Ghoul of my Dreams", "In Like Blunt" and "Time and Punishment".
Ammonia Pine, along with the rest of FOWL, has been recruited by the Villain League to counter Emperor Fang's move of recruiting Negaduck into the Fang Empire.