It would be considered a fetish if the only way you can achieve sexual gratification is through tickling.
Anti-social personality disorder isn't something to joke about. Most serial killers had anti-social personality disorder. These people aren't capable of empathizing with others... or feeling emotions in general.
I find when serial killers are diagnosed with Anti-Social Disorder, it's in an attempt to plead "insanity" in court. Anti-Social Disorder could be applied to many people that don't really have anything wrong with them.




