You can never learn to use magic, and you react badly to any user of magic. Make a self-control roll whenever you are in the presence of magic. This roll is at -3 if you are to be the target of friendly magic, and -6 if you are the target of hostile magic. (The magic does not have to be real, if you believe in it!)
You are deathly afraid of infection, or just of dirt and filth. Make a self-control roll when you must do something that might get you dirty. Roll at -5 to eat any unaccustomed food. You should act as “finicky” as possible.
You are terrified by the idea of death. Make a self-control roll in the presence of any dead body (animals don’t count, but portions of human bodies do). Roll at -4 if the body is that of someone you know, or -6 if the body is unnaturally animated in some way. A ghost (or apparent ghost) also requires a roll at -6.
varies; Make a self-control roll whenever it would be wise to deviate from your goal. If you fail, you continue to pursue your Obsession, regardless of the consequences.