Sexual intercourse
Sexual offenses

Sexual intercourse with a person against their will, or without their consent, is rape, but may also be called sexual assault; it is considered a serious crime in most countries. More than 90% of rape victims are female, 99% of rapists male, and only about 5% of rapists are strangers to the victims.

Most countries have age of consent laws which set the minimum legal age with whom an older person may engage in sexual intercourse, usually set at 16 to 18, but ranges from 12 to 20, years of age. In some societies, an age of consent is set by non-statutory custom or tradition. Sex with a person under the age of consent, regardless of their stated consent, is often considered sexual assault or statutory rape depending on differences in ages of the participants. Some countries treat any sex with a person of diminished or insufficient mental capacity to give consent, regardless of age, as rape.

Robert Francoeur et al. stated that "prior to the 1970s, rape definitions of sex often included only penile-vaginal sexual intercourse." Authors Pamela J. Kalbfleisch and Michael J. Cody stated that this made it so that if "sex means penile-vaginal intercourse, then rape means forced penile-vaginal intercourse, and other sexual behaviors – such as fondling a person's genitals without her or his consent, forced oral sex, and same-sex coercion – are not considered rape"; they stated that "although some other forms of forced sexual contact are included within the legal category of sodomy (e.g., anal penetration and oral-genital contact), many unwanted sexual contacts have no legal grounding as rape in some states". Ken Plumber argued that the legal meaning "of rape in most countries is unlawful sexual intercourse which means the penis must penetrate the vagina" and that "other forms of sexual violence towards women such as forced oral sex or anal intercourse, or the insertion of other objects into the vagina, constitute the 'less serious' crime of sexual assault".

Over time, the meaning of rape broadened in some parts of the world to include many types of sexual penetration, including anal intercourse, fellatio, cunnilingus, and penetration of the genitals or rectum by an inanimate object. Until 2012, the Federal Bureau of Investigation (FBI) still considered rape a crime solely committed by men against women. In 2012, they changed the meaning from "The carnal knowledge of a female forcibly and against her will" to "The penetration, no matter how slight, of the vagina or anus with any body part or object, or oral penetration by a sex organ of another person, without the consent of the victim." The meaning does not change federal or state criminal codes or impact charging and prosecution on the federal, state or local level, but instead assures that rape will be more accurately reported nationwide. In some instances, penetration is not required for the act to be categorized as rape.

In most societies around the world, the concept of incest exists and is criminalized. James Roffee, a senior lecturer in criminology at Monash University, addressed potential harm associated with familial sexual activity, such as resulting children born with deficiencies. However, the law is more concerned with protecting the rights of people who are potentially subjected to such abuse. This is why familial sexual relationships are criminalized, even if all parties are consensual. There are laws prohibiting all kinds of sexual activity between relatives, not necessarily penetrative sex. These laws refer to grandparents, parents, children, siblings, aunts and uncles. There are differences between states in terms of the severity of punishments and what they consider to be a relative, including biological parents, step-parents, adoptive parents and half-siblings.

Another sexual matter concerning consent is zoophilia, which is a paraphilia involving sexual activity between human and non-human animals, or a fixation on such practice. Human sexual activity with non-human animals is not outlawed in some jurisdictions, but it is illegal in others under animal abuse laws or laws dealing with crimes against nature.
length_constraints:number_words[263], detectable_format:constrained_response