While engaging in clinical practices with those who have dissociative identity disorder, we quite often encounter a type of personality states with frequent display of aggressiveness and/or self-destructiveness. It typically shows difficulty in being identified or “located”, as their appearance is rather unpredictable and their name is often unknown. The patient (or his/her main personality, rather) states that unlike other parts of personalities with their identifying name and their respective profiles，he/she does not have any first-hand knowledge about that type of personality state.
In this communication, I would like to call this type of personalities “SP (shadowy personality)” as it is often the way the patients describe it, with an implication that it is not quite tangible, and it often takes a shape of just a shadow or grayish substance. Some patients literally call it a “shadow” or “shadow-like”, and others refer to them as dark or black figure, without clear countenance or facial expressions.