The two sets of people involved often meet either randomly or arrange to meet up beforehand over the Internet. Female masturbation involves the stroking or rubbing of a woman vulva, especially her clitoris, with an index or middle fingers, or both. Some masturbate only using pressure applied to the clitoris without direct contact, for example by pressing the palm or ball of the hand against underwear or other clothing. The naked appearance of actress Demi Moore in the advanced stage of pregnancy on the cover of Vanity Fair magazine in 1991 marked the beginning of a period which has since seen pregnancy presented by celebrities as a glamorous state of living, while also creating a market for photographers to produce images of pregnant mothers, and for fashion stylists to introduce pregnancy styling to their business. In these research publications, it is suggested that real female ejaculation is the release of a very scanty, thick, and whitish fluid from the female prostate, while the squirting or gushing shown frequently in pornography is a different phenomenon, the expulsion of clear and abundant fluid, which has been shown to be a diluted fluid from the urinary bladder. Group sex also occurs in populations of non-human animals such as bonobo apes and chimpanzees. A pornographic work momporn is characterized as hardcore if it has any hardcore content. Although there may be no connection between coprophilia and sadomasochism , the limited data on the former comes from studies of the latter. They signal the presence hentai videos of estrogen and the presence of sufficient fat stores gay twink porn for pregnancy and lactation. Others consider the position to involve the man squatting over his reclined partner while the testicles are repeatedly raised and lowered into the mouth. Some people get sexual pleasure by inserting objects, such as urethral sounds, into the urethra , a practice known as urethral play or sounding. The fantasy is typically based around one or more larger beings dominating a smaller being.