As the quotation from Butrica suggests and an article by W. A. Krenkel shows irrumatio was a widespread sexual practice in the Roman Empire (where homosexuality was accepted as a normal trait for a certain time period). J. N. Adams states that "it was a standard joke to speak of irrumatio as a means of silencing someone" . Oral sex of all kinds were considered to be acts of defilement: the mouth had a particularly defined role as the organ of oratory, as in Greece, to participate in the central public sphere, discursive powers were of great importance. Thus, to penetrate the mouth could be taken to be a sign of massive power differential within a relationship. Remaining frescos from the Roman city of Pompeii that was destroyed by an eruption of a volcano named Vesuvius, which kept the buildings well-preserved, demonstrate that irrumatio was one of the specific Roman sexual acts, the others being fututio, fellatio, pedicatio and cunnilingus. This was probably because the extant frescos appear to be in bathhouses and brothels: oral sex was something usually practiced with prostitutes because of their lowly status.
Still, C. A. Williams argues that it was accepted as a degrading act, even more so than anal sex . S. Tarkovsky states that despite being popular, it was thought to be a hostile act, "taken directly from the Greek, whereby the Greek men would have to force the fellatio by violence" . Furthermore as A. Richlin has shown in an article in the Journal of the History of Sexuality it was also accepted as "oral rape", a punitive act against homosexuality .
Roman historian Suetonius has a passage in his De Vita Caesarum which inconclusively states that Roman emperor Tiberius took great pleasure from forcing women, even those of rank, to perform irrumatio.
Forced irrumatio is often called "Egyptian Rape" or simply “Egyptian.” This goes back to the time of the Crusades when Mamluks were alleged to force their Christian captives to do this.
The first type of irrumatio involves sexual stimulation through the thrusting of the penis between the legs or the (upper) thighs of the partner or between the abdomens of two partners. Lubrication can be used for this purpose. Sometimes the term masturbation is used to describe such stimulation. Like other types of non-penetrative sex, also known as outercourse or dry sex, it is a safe sex technique. This type of irrumatio is historically (i.e. in the Roman times) and usually performed by male partners and therefore is perceived as a homosexual act.
Several English and Latin terms are used to describe irrumation by thrusting the penis between the upper thighs: English method, college style, college sex, Princeton rub (also used for frot), Snoopy style, Harvard style, leggins, intercrural intercourse, interfemoral intercourse, coitus ante portas, coitus inter femora, coitus interfemoris etc. The act can be performed in four different ways with the receiving partner standing up or bending down, sitting on the lap of the active partner, lying down on the bed or on a table, and in pederasty.
In oral sex, irrumatio is performed by actively thrusting the male reproductive organ into the mouth of the partner. In slang, this act is called face sexing, throat sexing and skull sex.
As with fellatio, it may be performed to induce orgasm and ejaculation of semen. It can also be used as foreplay prior to vaginal or anal forms of intercourse. However, the passive partner might experience certain difficulties compared to less-aggressive fellatio, such as feeling as if s/he is abused, boredom, uncomforting reflexes, coughing up saliva, vomiting, being unable to breathe, etc. One method for the passive partner to overcome such difficulties is using the so-called stopper technique by wrapping one hand around the lower shaft of the penis thus being able to control its movement.
Fellatio and irrumatio can be used interchangeably during oral sex. Indeed the distinction between fellatio and irrumatio has vanished in modern English and the latter term has fallen out of widespread use.
In pornography, certain work focusing on gagging (the gag reflex) clearly includes such a point of view. In such work, the females become subject to what is usually portrayed as degrading irrumatio in mostly kneeling down or lying backwards positions. It is customary to make females deep throat the entire penis and then receive facials. Many scenes include flowing of saliva, pre-ejaculate and semen from the actress's mouth, tears from her eyes, mascara running and in more extreme cases, mucus and actual vomiting. Examples include pornographic movies Throat Gaggers and Gag Factor. The Max Hardcore pornographic movies show females sucking on or swallowing their own vomit after being subjected to extreme deep-throating. There are also several themed web sites such as Make Them Gag and Throat Jobs. Blow bangs and bukkake are common, but not necessary elements in such work.