You have a seething hatred for someone or something. The hatred is so strong that you have trouble controlling yourself. The hatred doesn't have to be limited to a single individual, but if it is for a single person, then the hatred is so strong that you may just wish for them to be dead. If you ever come across something or someone you hate then you must pass a check against this trait in order to not immediately attack the person, although perhaps not to lethally injure them, but at least give them a good beating. If your trait value is -1 or -2, you may limit yourself to only verbal attacks.