Not so fun fact: there’s a bacterium transmissible to humans through cat waste, toxoplasma gondii. One of the symptoms of a toxoplasmosis infection is a complete inability to smell cat urine.

That’s what I first thought of when reading your story, because cat hoarders often get toxoplasmosis and thus have no idea that they smell bad. The disease can cause all kinds of neurological symptoms and also cause birth defects when pregnant women get infected.