Some women who engage in same-sex sexual activity may reject not only identifying as lesbians but as bisexual as well, while other women self-identification as lesbian may not align with their sexual orientation or sexual behavior; sexual identity is not necessarily the same as one sexual orientation or sexual behavior, due to various reasons, such as the fear of identifying their sexual orientation in a homophobic setting. The range of its individual characteristics is thereby wide. Transsexual people Transman pornography features performers who were born female and who medically transitioned to male. Group sex is sexual behavior involving more than two participants. Celebrity sex tapes are amateur or professionally-made recordings of sex acts, as performed by a celebrity and their partner. Some do not use the diapers at all, for arousal, or bladder and bowel movements. It has also been recommended as a form of foreplay or safer sex. A few extremely flexible males can reach and stimulate their penis with their tongue or lips, and so perform autofellatio. A sub-set of vaginal fisting attempts to photograph the female cervix immediately after the fist is removed from the now-gaping vagina. Entacle erotica describes a type of pornography most commonly found in Japan which integrates traditional pornography with elements of bestiality and a fantasy, horror, or science-fiction theme. Terminology for roles varies widely within the various BDSM subcultures. Two women tapegagged and cuffed to iron bars Bondage and Discipline are two aspects of BDSM that do not seem to relate to each other because of the type of activities involved, but they have conceptual similarities, and that is why they appear jointly. Sometimes one or more fingers may be inserted into the vagina to stroke its frontal wall where the G-spot may be located. Examples of heterosexual pornographic real celebrity porn film series featuring creampies include Cream Filled Teens and Internal Cumbustion. As a result, little in history was documented to give an accurate description of how female homosexuality is expressed.