Board Thread:Questions and Answers/@comment-7708862-20130402005255/@comment-1351982-20130502150237

Gin likely had Antisocial personality disorder or ASPD. ASPD is defined as, "is a mental health condition in which a person has a long-term pattern of manipulating, exploiting, or violating the rights of others. This behavior is often criminal."

Some signs of ASPD may include:


 * Be able to act witty and charming
 * Be good at flattery and manipulating other people's emotions
 * Break the law repeatedly
 * Disregard the safety of self and others
 * Have problems with substance abuse
 * Lie, steal, and fight often
 * Not show guilt or remorse
 * Often be angry or arrogant

Gin shares similar traits with at least 6 out of the 8 common traits listed, and furthermore some of the "believed" potential causes of ASPD are, "...Genetic factors and environmental factors, such as child abuse, are believed to contribute to the development of this condition. People with an antisocial or alcoholic parent are at increased risk. Far more men than women are affected. The condition is common among people who are in prison."

Finally, Kubo said he was confused with Gin's popularity (particularly with women), which further leads me to believe that he was written in a way to be unappealing, so that his relationship with Rangiku was even more confusing.