As a result, little in history was documented to give an accurate description of how female homosexuality is expressed. They further argue that setting a discrete line between safe and not-safe activities ideologically denies consenting adults the right to evaluate risks vs rewards for themselves; that some adults will be drawn to certain activities regardless of the risk; and that BDSM play—particularly higher-risk play or edgeplay—should be treated with the same regard as extreme sports, with both respect and the demand that practitioners educate themselves and practice the higher-risk activities to decrease risk. It is sometimes combined with BDSM features. This may relate to fetishes such as voyeurism or cuckolding. Women in homosexual relationships responded to this designation either by hiding their personal lives or accepting the label of outcast and creating a subculture and identity that developed in Europe and the United States. Oral sex pornography frequently features a person performing fellatio, and less frequently cunnilingus. Examples of heterosexual pornographic film series featuring creampies include Cream Filled Teens and Internal Cumbustion. Since the 1980s, many practitioners and organizations have adopted the motto safe, sane and consensual, commonly abbreviated as SSC, which means that everything is based on safe activities, that all participants be of sufficiently sound/sane mind to consent, and that all participants do consent. In some scenes or relationships it may be impossible for consent to be withdrawn in the middle of a scene, or the bottom may have the ability to revoke consent for a relationship as a whole, but not for a particular scene. Hardcore pornography is pornography that depicts penetration or extreme fetish acts, or both. The buttocks in human females thus contain more adipose tissue than in males, especially after puberty. Terminology for roles varies widely gay cock within the various BDSM subcultures. In human sexuality, lesbian milfs a threesome is sexual activity that involves three people at the same time.