“Rape is a type of sexual assault usually involving sexual intercourse or other forms of sexual penetration initiated against one or more individuals without the consent of those individuals...Sexual penetration is the insertion of a body part or other object into a body orifice, such as the vagina, anus or mouth...”
http://en.wikipedia.org/wiki/Rape
Again, there are very few cases of male oral rape on a female, or another male. There is too much potential for unintended consequences. These cases are usually drug induced rape where the woman has no opportunity for defense of any kind.
Although the NY police orally raped a guy with their batons.