The industry generally refers to such films as adult films, which is part of adult entertainment. Clothed female, naked male pornography features naked men and clothed women; typically, the women humiliate and abuse the men or perform fellatio and/or handjobs on the men. What seems clear from the historical record is that much of the lesbian material in pornographic texts was intended for a male readership. The porn hentai porn industry and viewing public were shocked by the then-taboo spectacle of a white woman having sex with a black man. Masturbation is the self-sexual stimulation of the genitals for sexual arousal or other sexual pleasure, usually to the point of orgasm. Perhaps following the example set by gay pornography, they have become a popular subgenre within heterosexual pornography since the turn of the century, featuring both vaginal and anal ejaculations. As a form of non-penetrative sex, it can be done for its own enjoyment or as foreplay. It contains graphic sexual activity and visible penetration. In 1988, a sex tape caused significant damage to Rob Lowe career. Sometimes one or more fingers may be inserted into the vagina to stroke its frontal wall where the G-spot may be located. Rape pornography features performers simulating rape. Such ejaculation can be done by mammary intercourse, or masturbation over the other person, or result from the withdrawal of the penis from a partner mouth as he is ejaculating following fellatio, irrumatio, or intercourse. Internal nude milfs ejaculation shots are a comparatively recent development in pornography; they are not found in early pornographic films. Some straight actors have started acting in gay porn only to be accused of being gay while others first step was to strictly do solo scenes. The most common male masturbation technique is simply to hold the penis with a loose fist and then to move the hand up and down the shaft. Sexual orientation Pornography features an increasing variety of combinations of actors by their sexual orientation such as lesbian, gay cock gay, bisexual, and transsexuals in addition to traditional heterosexual roles.