Double Stuffed , Double Vaginal , or Double Anal pornography involves the penetration of one orifice by two penises or other objects. This can, however, redirect semen into the bladder . Examples of heterosexual pornographic film series featuring creampies include Cream Filled Teens and Internal Cumbustion. Rape pornography features performers simulating rape. Additionally, the buttocks give an indication of the shape and size of the pelvis, which impacts reproductive capability. Sexual orientation Pornography features an increasing variety of combinations of actors by their sexual orientation such as lesbian, gay, bisexual, and transsexuals in addition to traditional heterosexual roles. Women oriented pornography is sometimes referred to as sex positive pornography. Bukkake pornography involves a performer, usually female, onto whom several videos gay men or women ejaculate, usually on the face. The phrase buttered bun is sometimes used to refer to the owner of the orifice in question. Jerk off instruction features a performer encouraging or instructing the viewer to masturbate, often culminating in a countdown at the end of which the viewer is invited to induce orgasm. Bukkake is a sex act portrayed in pornographic films, in which several men ejaculate on a woman, or another man. Mammary intercourse is known as titty-fucking, titfuck, or a titjob in the United States, as well as tit wank or French fuck in the United Kingdom - the latter term dating back to the 1930s; while a more jocular equivalent is a trip down mammary lane. It is also followed by dedicated industry publications and trade groups as well as the mainstream press, private organizations , government agencies, and political organizations. The term applies to the depiction of the act rather than the act itself, and so does not include live exhibitions like sex shows and striptease. Tentacle erotica can be consensual, but frequently contains elements of non-consensual sex. The other person may do the same during or after.