Here is a little test. Here is the DSM criteria for several personality disorders but I have left the disorders off. Going by traits alone since xn will NEVER be diagnosed, I am sure, I blindly selected EVERYTHING under NPD, and half under anti-social and half under psychopathy. I believe xn to be an extremely malignant narc. The only thing keeping him from full blown psychopathy is not trouble with the law (that I am aware of). Let me know how your SO score.
BTW, this is a test you don't want to make a perfect score on

1 Failure to conform to social norms with respect to lawful behaviors
2 Deceitfulness
3 Impulsivity or failure to plan ahead
4 Irritability and aggressiveness as indicated by repeated physical fights or assaults
5 Reckless disregard for the safety of self or others
6 Consistent irresponsibility as indicated by repeated failure to sustain consistent work behavior or honor financial obligations
7 Lack of remorse as indicated by being indifferent about having hurt, mistreated or stolen from another.
8 Manipulativeness
9 Insincerity
10 Egocentricity
11 Lack of guilt
12 Glib and superficial charm
13 Grandiose estimation of self
14 Need for stimulation
15 Pathological lying
16 Cunning and manipulativeness
17 Lack of remorse or guilt
18 Shallow affect (superficial emotional responsiveness)
19 Callousness and lack of empathy
20 Parasitic lifestyle
21 Poor behavioral controls
22 Sexual promiscuity
23 Early behavioral problems
24 Lack of realistic long term goals
25 Impulsivity
26 Irresponsibility
27 Failure to accept responsibility for own actions
28 Many short term marital relationships
29 Juvenile delinquency
30 Revocation of conational release
31 Criminal versatility
32 Frantic efforts to avoid real or imagined abandonment. .
33 A pattern of unstable and intense interpersonal relationships characterized by alternating between extremes of idealization and devaluation.
34 Identity disturbance: markedly and persistently unstable self-image or sense of self.
35 Impulsivity in at least two areas that are potentially self-damaging (e.g., spending, sex, substance abuse, reckless driving, binge eating).
36 Recurrent suicidal behavior, gestures, or threats, or self-mutilating behavior
37 Affective instability due to a marked reactivity of mood
38 Chronic feelings of emptiness
39 Inappropriate, intense anger or difficulty controlling anger (e.g., frequent displays of temper, constant anger, recurrent physical fights)
40 Transient, stress-related paranoid ideation or severe dissociative symptoms
41 "An grandiose sense of self-importance (e.g., exaggerates achievements and talents, expects to be recognized as superior without commensurate achievements)
42 "Preoccupation with fantasies of unlimited success, power, brilliance, beauty, or ideal love
43 Believes he is special and unique and can only be understood by with other special or high status people or institutions
44 "Requires excessive admiration
45 "Has a sense of entitlement
46 Selfishly takes advantage of others to achieve his own ends
47 Lacks empathy
48 "Is often envious of others or believes that others are envious of him
49 Shows arrogant, haughty, patronizing, or contemptuous behaviors or attitudes
50 Exibitionist behavior
51 Constant seeking of reassurance or approval
52 Excessive dramatics with exaggerated displays of emotions.
53 Excessive sensitivity to criticism or disapproval.
54 Inappropriately seductive appearance or behavior.
55 Excessive concern with physical appearance.
56 Making rash decisions
57 A need to be the center of attention.
58 Low tolerance for frustration or delayed gratification.
59 Rapidly shifting emotional states that may appear superficial or exaggerated to others.
60 Tendency to believe that relationships are more intimate than they actually are.