Brief Psychological Analysis of Saeko Busujima
Sadistic personality disorder can be diagnosed under this DSM III-R criteria:
A) A pervasive pattern of cruel, demeaning, and aggressive behavior, beginning by early adulthood, as indicated by the repeated occurrence of at least four of the following:
1.Has used physical cruelty or violence for the purpose of establishing dominance in a relationship (not merely to achieve some non-interpersonal goal, such as striking someone in order to rob him/her).
2.Humiliates or demeans people in the presence of others.
3.Has treated or disciplined someone under his/her control unusually harshly.
4.Is amused by, or takes pleasure in, the psychological or physical suffering of others (including animals).
5.Has lied for the purpose of harming or inflicting pain on others (not merely to achieve some other goal).
6.Gets other people to do what he/she wants by frightening them (through intimidation or even terror).
7.Restricts the autonomy of people with whom he or she has a close relationship, e.g., will not let spouse leave the house unaccompanied.
8.Is fascinated by violence, weapons, injury, or torture.
B) The behavior in A has not been directed toward only one person (e.g., spouse, one child) and has not been solely for the purpose of sexual arousal.
Clearly, Saeko possesses a sadistic personality. One could also say that she is antisocial and somewhat psychopathic.
What is the reason behind her flaws?
I have some theories.
She mentions during the shrine scene to Takashi amidst explaining her sadistic personality that when she harms people, she is "letting the rage out". Where is this rage coming from? What could push somebody's mentality and emotions so far that she is in a constant state of internal rage?
First of all, it seems like she lives in a household without a mother (she never mentions her mother, and has stated that her father is the only family she has). It seems like her father is the only parental unit of the family. One could go on and on about the detrimental effects of not having a mother figure. Such effects include negative self-image, social confusion, and chronic depression. All of these detrimental effects result mostly from an inherent void that is not being filled by a maternal figure in one's life.
This "rage" Saeko has could have also resulted from childhood abuse. We can assume her father is a strict, conservative martial arts instructor who runs a dojo. It would not be wild to also assume that he resorted to physical discipline while rearing Saeko. Excessive physical discipline during childhood not only abuses the body, but also the mind. Many studies document that people who suffered constant physical and emotional abuse during childhood often become numb to normal emotional responses while developing sadistic tendencies. These sadistic tendencies usually result from a constant stream of anger from a childhood full of abuse. This anger is vented out in the form of violence and domination (dominance in what ever form possible; as long as the individual is in complete control of his/her situation).
All of these factors could have contributed to Saeko's "rage". It is obvious she feels guilty of her personal demons. She resents the fact that she enjoys hurting people, and she tries to compensate for this flaw by behaving in a well-mannered fashion in public. Ofcourse, this facade could also be another tool of hers to attain what she wants by controlling and manipulating people's emotional responses towards her.
She is currently experiencing catharsis by killing as many of THEM as she desires to. Whether or not it helps her or worsens her condition is up to what she comprehends of her experiences in this zombie apocalypse. What she really requires is a multitude of psycho-therapy sessions.