Your moods are totally unpredictable. One minute you are happy and laughing, the next you are ferociously angry or burst into tears. People who know you are extremely wary around you, since they do not know how you will react to anything they do or say, so they react to you at -2. If you are in a position of authority, or have the power to get your own way due to physical or magical power, your subordinates are afraid of you and react at -4.
In any stressful or emotionally-charged situation, roll 1d. On an even number, your emotions stay the same. On an odd roll, your emotions become completely different. You may also make this roll whenever you see fit, and the GM can ask for it at any time.