The cerebral narcissist renders himself unattractive to his partner by gaining weight, neglecting his body and personal hygiene, not attending to his rotting teeth and crumbling health, and dressing shabbily.
This self-inflicted and ostentatious corporeal abuse has the effect of bringing sexual and physical intimacy to a screeching halt and forcing his mate or spouse into patterns of behavior and lifestyle alien to her nature: if she is a codependent and fears abandonment she abjures sex altogether (becomes asexual) and if she is not, she is forced into adultery and promiscuity.
This kind of narcissist is afraid of encounters with the opposite sex and is even more afraid of emotional involvement or commitment that he fancies himself prone to develop following a sexual encounter.
In general, such a narcissist withdraws not only sexually – but also emotionally. If married – he loses all overt interest in his spouse, sexual or otherwise.
He confines himself to his world and makes sure that he is sufficiently busy to preclude any interaction with his nearest (and supposedly dearest).
He becomes completely immersed in "big projects", lifelong plans, a vision, or a cause – all very rewarding narcissistically and all very demanding and time consuming.
In such circumstances, sex inevitably becomes an obligation, a necessity, or a maintenance chore reluctantly undertaken to preserve his sources of supply (his family or household).
The cerebral narcissist does not enjoy sex and by far prefers masturbation or "objective", emotionless sex, like consuming porn, or, much more rarely, group sex, or visiting prostitutes.
“I practice the safest and most thrilling sex there is: masturbating to pornography”.
Actually, he uses his mate or spouse as an "alibi", a shield against the attentions of other women, an insurance policy which preserves his virile image while making it socially and morally commendable for him to avoid any intimate or sexual contact with others, ostentatiously ignoring women other than his wife (a form of sadistic aggression I call “ostentatious fidelity”).
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