People with antisocial personality disorder (ASPD) can be witty, charming, and fun to be around -- but they also lie and exploit others. ASPD makes people uncaring. Someone with the disorder may act rashly, destructively, and unsafely without feeling guilty when their actions hurt other people.
Experts don’t agree on whether antisocial personality disorder and psychopathy (i.e. "a psychopath") are the same thing. Either way, ASPD is uncommon, affecting just .6% of the population.