BEHAVIOR... Better than a mood ring...

Does he/she persistently lie to you or steal from you?

Do you get the feeling that they have no remorse for hurting people?

Do they have a childhood diagnosis of conduct disorder?

Are you fearful of your safety? Is he/she prone to violence and/or aggressive behavior?

Is he/she unable to keep and maintain friendships? 

Have you noticed that he/she has an extreme sense of entitlement, often putting others needs last or not considering them at all?

Do you believe him/her when they compliment you, or does it seem superficial and manipulative?

Is he/she wreckless and impulsive? 

Does it seem as they have no self control? 

Do they have recurring difficulties with the law because of this?

If you answered "yes" to any of these questions, you are unfortunately dealing with somebody who suffers from Antisocial Personality Disorder (ASPD).  One just needs to look at a persons history (legal, employment, family) and pay attention to their current life situation. Do they maintain a heavy focus on using alcohol or other substances?

Do they spend an inordinate amount of time in attempts at creativity? (Writing stories or poetry on social networking sites)..

Is their mood shifts evident in their attempt at creativity?  (Focus on love, loss, life, sex?)

It's important to evaluate the answers to the information as being observed.  Many that suffer ASPD and BPD try to escape their chemical imbalance through creating a "delusional" or "Fantasy" existence.  By nature of their disorder they seek to portray the existence as reality specifically in an environment that allows them to maintain anonymity thus protecting the frailty of the existence they have created. One can pay close attention to the writings the individual composes and will notice the mood swings that are characteristic with their mental illness.  When feeling "stable" whether on medication or a hiatus in the biochemical storm that they routinely experience, you will notice a high degree of fictional creativity as they mold their delusion around their ideal life.  They will embellish facts of their own life to bring attention of those groups or individuals (targets) that they choose to be their audience.  Male suffers of the disorder,will focus on females, alcohol and sex.  Many times they will compose stories that find themselves and a female being the last two people on earth(i.e post apocalyptic back drop). Other times they will portray a life of highly romantic love focusing on having unlimited money to show such love. One commonality in their writings is a high acclaim and use off alcohol whether wine, beer or whiskey in everyday life.  Their is an extremely high incidence of co-morning alcoholism with this and other mental illnesses.  More importantly however, you can track the cycles of their disorder based on the prose they present. When shifting to a manic, uncontrolled state, the frequency of their compilation of poetry increases... The majority of which places emphasis on the loss of love, the ability of the composer to love better than anyone, sex and how he/she doesn't care and can bring bodily harm to another (this part occurs at the precipice of a manic break which often is a precursor to running afoul of the law.). 

If one just takes the time to answer the questions and then pay attention to the the time and content placed into the creation of their delusion then you can not fall prey to their manipulation.  Don't be mistaken, they have no other motive than to "use" another as evident in their legal history, broken relationships, poor employment history.. Truth is, what type of person has the time to devote to the creation of delusional existences (that doesn't get paid to do so) heavily focused on sex and alcohol with a history of legal issues (40 + legal runnins, many DUI's, Assault and Battery charges to including on a female and a history of psychiatric hospital admissions)?  An unemployed alcoholic who refuses to follow the treatment plan as established by a psychiatrist.  I could name names as examples with specific illustrations but I believe the warning is very clear.  See the signs, stay away or be abused by the person.  Simple as that.