This is also the case in many relationships not considering themselves as sadomasochistic; it is considered to be a part of BDSM if it is practiced purposefully. Squirt pornography involves women ejaculating. Masturbation has been depicted in art momporn since prehistoric times and is mentioned and discussed in very early writings. Voyeur or peeping Tom pornography is usually more staged anime hentai with the subjects aware of the cameras, sometimes openly including cartoon porn videos this exhibitionist awareness. When all regions of the face are included, facial cum shots comprise approximately 62% of scenes where external ejaculation occurs. Through the 1990s, mainstream movie and television actors have been more willing to portray homosexuality, as the threat of any backlash against their careers has lessened and society acceptance of gay and lesbian people has increased. Strictly speaking, bondage means binding the partner by tying their appendages together; for example, by the use of handcuffs or by lashing their arms to an object. Insertion in pornography features women inserting various odd objects into their anus or vaginas. They may repeat this cycle multiple times. Teacher and Student or Boss and Secretary pornography involves sexualized situations which take place between an authority figure, such as a teacher or boss, and an gay boy porn underling, such celebrity gossip as a student or secretary, often fake. Sexual scenarios may involve male domination, female submission, exhibitionism and erotic entertainment. There is also some evidence that pornography can be used to treat voyeurism. The term is a slang word that originated in the gay community and comes from the equestrian term bareback, which refers to the practice of riding a horse without a saddle. Technically this is a form of exhibitionism rather than group sex per se. Caro rejected that as being a necessary conclusion, stating that female fatty deposits on the hips improve individual fitness of the female, regardless of sexual selection. Other forms of anal sex include fingering, the use of sex toys for anal penetration, oral sex performed on the anus , and pegging.