In the modern, real-world incarnation of the no/low sex spectrum we find asexual people, a group increasingly interested in “coming out” and staking their claim on the social landscape. A defining feature of asexuality is little or no sexual attraction to other people - in short, no lustful lure for others.
Not surprisingly, many asexual people also exhibit very little sex drive or sexual interest whatsoever (including no masturbation), although some may still have some “solitary” desire.  Thus, some asexual people may still evince some sexual drive but it is not connected to others.     
Sheldon Cooper from the Big Bang Theory Recent research has suggested that perhaps as many as one per cent of the population—with more women than men—are asexual.  Research also suggests that the origins of asexuality, like traditional sexual orientations, are at least partly rooted in early development.
Researchers have also begun to examine a variety of issues related to asexuality, including how some asexual people are content to “fly under the radar,” socially speaking, while others may form a strong asexual identity and “come out” to others, and how asexual people may be the subject of prejudice and discrimination.  In the latter case, recent research suggests that the sexual majority may view asexual people more negatively than other sexual minorities.

Asexual people, particularly if they are comfortable with themselves, have also recently challenged health professionals, including writers of the latest edition of the Diagnostic and Statistical Manual of Mental Disorders (or DSM), as to what it means to have a sexual disorder.  For example, there is now a provision in the recent DSM that allows self-identified asexual people to avoid being diagnosed with having a sexual disorder. 
As I suggest in my book, Understanding Asexuality, there are many reasons why those interested in sex—including sex researchers/educators—should try to understand asexual people and their view of the world. First, studying asexual people provides information on a relatively unstudied group, and knowledge of this minority may help asexual people understand themselves better and ease their negotiation through a complex and foreign sexual world.

Studying asexuality also provides a unique window on sexuality and its mysteries, including its complex relationship to love and romance.  For example, although some asexual people do not want romantic relationships—one person on AVEN, the most popular online forum for asexual people, writes succinctly “Never had a relationship, never want one” — many asexual people desire romantic relationships, even if they eschew sexual ones.  Another AVEN participant writes: “I am now in a relationship with a heterosexual person, I don't know how it will work out but I am trying to be positive about it and keep the focus on what we have in common rather than what we don't have in common…”
Given that asexual people often want a romantic relationship (despite its challenges), they provide a model of how romantic love can be de-coupled from sex, and such a model also holds for sexual people. Indeed, the popularity of movies in the romance genre—e.g. two (burly) straight men forming a deep bond— demonstrates the usefulness of the romance versus sex model of human attachment.