Oral sex pornography frequently features a person performing fellatio, and less frequently cunnilingus. Barebacking usually refers to a conscious and deliberate choice to forgo condoms. Preggo pornography features pregnant performers and may include erotic lactation as a fetish. Normal quantities of ejaculate range from 1.5 to 5.0 milliliters . Older names for a pornographic film include stag film, and blue movie. The concept of lesbian, to differentiate women with a shared sexual orientation, is a 20th-century construct. Lolita pornography features women who are 18 years old or slightly older, lesbian hentai who pretend to be underage teen girls. Solo pornography recognized with AVN Awards include the All Alone series and All Natural: Glamour Solos. Female dominance refers to BDSM relationships and BDSM scenes in which the dominant partner is female. Some men also enjoy anal stimulation, with fingers or otherwise, without any prostate stimulation. This can, however, redirect semen into the bladder . It is also known colloquially as gushing or squirting, although these are considered to be different phenomena in some research publications. 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 gay twinks 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. Group sex most commonly takes place in a private sex party or semi-public swinger gathering, but may also take place at massage parlors or brothels or, in some jurisdictions, at purpose-built locations such as sex clubs. The definition clash also appears with the English definition of yuri as any lesbian relationship, as opposed to its sexually explicit definition in Japan. The smotherbox is porn milf placed on a stable surface. Sadomasochism is practiced in isolation relatively rarely, though some masochists report biting, pinching, or even stun-gunning themselves as a prelude to, or as part of, masturbation.