This ought to answer your question, there are also numerous external links on this topic available via the link: From http://en.wikipedia.org/wiki/Necropheliac Necrophilia according to the DSM IV, is a paraphilia characterized by a sexual attraction to corpses. Figuratively, the term "necrophilia" describes an inordinate desire to control another person, usually in the context of a romantic or interpersonal relationship; the accusation is that the person is so interpersonally controlling as to be better-suited to relationships with nonresponsive people. Necrophilia has also been a motive for some serial killers, including murderers Ed Gein and Jeffrey Dahmer, who ate his victims after killing them. Several other murderers have described drawing sexual excitement from killing, as well, such as Karla Faye Tucker, who claimed to have an orgasm with each swing of the axe she used to kill Jerry Lynn Dean. In some cases, necrophiliacs work in the funeral business, presumably for the facile access to human corpses. Consensuality issue A sexual act with a corpse is generally considered socially unacceptable; the presumption being that the person would not have consented to the act while alive, it amounts to the rape of a dead person. Virtually all human societies condemn abuse of the dead as a form of symbolic disrespect. In rare cases, however, necrophiliac acts can be consensual: for example, in the Armin Meiwes case, the victim gave his consent to the mutilation and death inflicted upon him. Necrophilia in neo-psychoanalysis In the analytic social psychology of Erich Fromm necrophilia is a character orientation which shows an increasing tendency toward destructiveness. Used in a non-sexual sense Erich Fromm understood necrophilia as an everyday behavior which is not an expression of a biologically fixated death instinct, but the consequence of a life without being really alive. For Erich Fromm necrophilia is the opposite of biophilia. The lack of love in the western society leads to necrophilia. Symbols of the necrophile are façades made of concrete and steel, modern weapon systems, the idolatry of the technology of the megamachine (technophilia), the wasting of resources in consumerism and the treatment of people as things in bureaucratism. Necrophilia in the arts While not necrophilia, romantic connections between love and death are a frequent theme in Western artistic expression. The Shakespeare tragedy Romeo and Juliet ends with the young lovers united in death. Edgar Allen Poe once described the death of a beautiful young woman to be one of the most beautiful images. (By this, he was not saying that it is a good thing for young women to die; to him melancholy and pain were sources of beauty.) Many alternative rock artists also focus on the connection between romantic love and death, despair, and the occult; in Europe, the most notable example is Him, and more generally the artists of the love metal movement. A comparable American analogue might be Stabbing Westward, a goth rock band whose songs dealt with despair, drug abuse, sexual abuse, death, and romantic love, often in conjunction. A second Goth rock band known as the Murderdolls, lead by Wednesday 13, has created a life style out of singing about Necrophilia and sexual acts with the dead. An extension of the emotional connection between love and death is love for a person, which remains after death. Some ghost stories focus on a deceased person's undying love for a living individual, manifest literally in the form of a palpable ghost or poltergeist. While it is considered a romantic image for a person to die "in the arms" of a lover, sexual activity with the dead is usually considered taboo, but has appeared in recent film and music. Resurrection erotica is a set of artistic sub-genres wherein a person is brought back from a nonresponsive state (death, or a coma) by an expression, sometimes graphically physical, of romantic or sexual love. An example of this in fairy tale is the Sleeping Beauty parable. The controversial German film Nekromantik offers a graphic portrayal of sexual necrophilia, and the Canadian film Kissed is about a woman who works in a morgue and finds herself erotically drawn to the corpses she deals with. In the 1970s, shock rocker Alice Cooper recorded a couple of songs about necrophilia, "I Love the Dead", and "Cold Ethyl". In the 1980s and '90s, necrophilia emerged in the heavy metal sub-genres of death metal, black metal and goregrind. In 1993, a music video for Tom Petty's hit song "Last Dance with Mary-Jane" featured the singer simulating various romantic poses with a dead woman (played by Kim Basinger). Among animals Necrophilia appears to be common in animals, with a number of confirmed observations. Kees Moeliker made one of these observations while he was sitting in his office at the Natuurmuseum Rotterdam, when he heard the distinctive thud of a bird hitting the glass facade of the building. Upon inspection, he discovered a drake mallard lying dead about two meters from the building. Next to the downed bird there was a second drake mallard standing close by. As he observed the odd couple, the living drake picked at the corpse of the dead one for a few minutes and then, without provocation, it mounted the corpse and began copulating with it. The act of dead rape lasted for about 75 minutes, in which time, according to Moeliker, the living drake took two short breaks before resuming with copulating behavior. Moeliker surmised that at the time of the collision with the window the two mallards were engaged in a common motif in duck behavior which is called rape flight. "When one died the other one just went for it and didn't get any negative feedback -- well, didn't get any feedback," according to Moeliker. Source: Guardian, Research News, 2/8/05, Donald MacLeod. "Necrophilia among ducks ruffles research feathers".

there is no single cause, and the cumulative effects of nature and nurture are different in each necrophile. most self proclaimed necrophiles you might run into online seem to say they have always had a facination with death, or the body in repose, for most of their lives.

getting kissed by their grandmas. She was so close to death the grim reaper had her on speed dial.

Because they are nuts. ---I get rated down for telling the truth.

Getting turned on by sight of dead men or women or worse...

scared of rejection or has been rejected by the opossite sex. Also likes the non-reaction of the dead corpes