Rapemail is a Portmanteau of the words Rape and Blackmail. It refers to a phenomena of human manipulative behavior to use an untrue accusation of sexual assault in hopes of blackmailing a victim to get money, leverage, or other advantage out of a victim. Since we live in times where we are more sensitive to rape and rape victims, and in some cases rape can be difficult to prove using physical or forensic evidence, the charge can carry a large amount of weight and be used to either get the victim to accede the the accusers demands, or at least realize that proving their side of the story would be incredibly time consuming and difficult and accede. The demands can run the gamut from monetary compensation, to job positions, to any kind of advantage one would be willing to gain over the victim.
Rapemail is an odd phenomena, since it uses the portrayed victimization of the accuser as a form of leverage over the victim. Often the victim has little in the way of a defense to offer up, and accedes to the accusers demands. Often the accuser simply holds it over the victim's head, never reporting the alleged crime, as this would end the ability to blackmail. An offer of Rapemail can often go in the other direction for the accuser, as the victim can realize that the only way to terminate the blackmail is to end the life of the accuser, leading to violence or murder. An example of when this works out poorly is when a prostitute will use either sexual blackmail or rapemail as a form of coercion to extort further money out of a John. This can lead to the accuser ending up the victim of kidnapping or murder, as the victim of the extortion looks desperately for a way out of the scheme.
Other forms of sexual blackmail abound, such as threatening to tell the spouse, employer or community about a person's indiscretions, but rapemail is a bit further, since it casts the victim in a criminal light and threatens criminal as well as social consequences.
In the workplace, it can be used to force a promotion or higher position, using either actual sexual indiscretion as a threat or the threat of the accusation of rape. This has lead to a series of measures in large organizations, meant to curtail sexual harassment and actual sexual assault, being employed to helpfully prevent these types of affairs or threats. Policies such as authority figures not being allowed to have closed door meetings alone with an employee help to prevent the idea of an unwitnessed event becoming a bigger issue.
Rapemail is considered an unfortunate turn of events since it threatens to actually take away legitimacy from actual claims of sexual assault and harassment, which are already overwhelmingly underreported as many go silent because of concerns of shame, retaliation or overall embarrassment. This is the inherently tragic irony of this form of blackmail.