I am of the belief that more people have some form of OCD (“Obsessive Compulsive Disorder”) Than will let on.
Mine are related to possession, sociality, and smell.
Possession - I can’t abide the idea that any possession of mine (which is only a possession because I have at some point considered it worth having) could be stolen or damaged.
One example of how possession OCD manifests for me is - When I lock my car wireless-ly I will walk back to the driver door and pull the handle. I will walk away. I will walk back and pull the handle again (Because I DO NOT TRUST my memory of having already done so)
The Sociality one manifests itself by my hating the idea of smelling bad to somebody else, so I shower every single day, and wash my hands after I’ve touched food, and chew minty gum, and I loathe my own ability to sweat (how strange then that I can find sweat sexy on a woman)
The Smell one is easy. I have an acute sense of smell, and if I detect even a minuscule hint of an unpleasant smell I would not be able to spend a lot of time in the same room as it if not otherwise distracted by a more powerful sensory input. At sleep time, a time when most senses are at their most inactive, if there is a bad smell I am in a particular kind of hell.