Information: - In mammals, the vagina is a muscular and tubular part of the female genital tract, which in humans extends from the vulva to the cervix. The outer vaginal opening may be partly covered by a membrane called the hymen. At the deep end, the cervix (neck of the uterus) bulges into the vagina. The vagina allows for sexual intercourse and childbirth, and channels menstrual flow, which occurs periodically as part of the menstrual cycle. - A sex swing ( also known as a sling ) is a type of harness designed to allow sexual intercourse between one partner suspended by the swing and another who moves freely . Though there is considerable variety in the design , the most common sex swings have a support for the back , another for the buttocks , and stirrups for each leg , which can be adjusted whilst the user is suspended . The following types of sex swing exist : traditional swing , door swing , body swing , and fantasy swing . The body swing is suspended from one partner 's body . The door swing is mounted on a door . The fantasy swing is suspended from an eye bolt in the ceiling . - A strap-on dildo (also strap-on, strapon or dildo harness) is a dildo designed to be worn, usually with a harness, during sexual activity. Harnesses and dildos are made in a wide variety of styles, with variations in how the harness fits the wearer, how the dildo attaches to the harness, as well as various features intended to facilitate stimulation of the wearer or a sexual partner. - Modern humans ("Homo sapiens", primarily ssp. "Homo sapiens sapiens") are the only extant members of Hominina tribe (or human tribe), a branch of the tribe Hominini belonging to the family of great apes. They are characterized by erect posture and bipedal locomotion; manual dexterity and increased tool use, compared to other animals; and a general trend toward larger, more complex brains and societies. - Oral sex, sometimes referred to as oral intercourse, is sexual activity involving the stimulation of the genitalia of a person by another person using the mouth (including the lips, tongue or teeth) or throat. Cunnilingus is oral sex performed on a female, while fellatio is oral sex performed on a male. Anilingus, another form of oral sex, is oral stimulation of a person's anus. Oral stimulation of other parts of the body (as in kissing and licking) is usually not considered oral sex. - Anal sex or anal intercourse is generally the insertion and thrusting of the erect penis into a person's anus, or anus and rectum, for sexual pleasure. Other forms of anal sex include fingering, the use of sex toys for anal penetration, oral sex performed on the anus (anilingus), and pegging. Though the term "anal sex" most commonly means penile-anal penetration, sources sometimes use the term "anal intercourse" to refer exclusively to penile-anal penetration, and "anal sex" to refer to any form of anal sexual activity, especially between pairings as opposed to anal masturbation. - The buttocks (singular: "buttock") are two rounded portions of the anatomy, located on the posterior of the pelvic region of apes (including humans), and many other bipeds or quadrupeds, and comprise a layer of fat superimposed on the gluteus maximus and gluteus medius muscles. Physiologically, the buttocks enable weight to be taken off the feet while sitting. In many cultures, they play a role in sexual attraction. Many cultures have also used the buttocks as a primary target for corporal punishment, as the buttocks' layer of subcutaneous fat offers protection against injury while still allowing for the infliction of pain. There are several connotations of buttocks in art, fashion, culture and humor, and the English language is replete with many popular synonyms that range from polite colloquialisms ("posterior" or "bottom") to vulgar slang. In humans the buttocks are located between the lower back and the perineum. - The gluteus medius (or glutus medius), one of the three gluteal muscles, is a broad, thick, radiating muscle, situated on the outer surface of the pelvis. - A dildo is a sex toy, often explicitly phallic in appearance, intended for sexual penetration or other sexual activity during masturbation or with sex partners. - In human anatomy, the perineum (Late Latin, from Greek "perineos") is the region of the body between the pubic symphysis (pubic arch) and the coccyx (tail bone), including the perineal body and surrounding structures. There is some variability in how the boundaries are defined. - Sexual intercourse, or coitus or copulation, is principally the insertion and thrusting of the penis, usually when erect, into the vagina for sexual pleasure, reproduction, or both. This is also known as vaginal intercourse or vaginal sex. Other forms of penetrative sexual intercourse include anal sex (penetration of the anus by the penis), oral sex (penetration of the mouth by the penis or oral penetration of the female genitalia), fingering (sexual penetration by the fingers), and penetration by use of a dildo (especially a strap-on dildo). These activities involve physical intimacy between two or more individuals and are usually used among humans solely for physical or emotional pleasure and commonly contribute to human bonding. - Physical intimacy is sensual proximity or touching. It is an act or reaction, such as an expression of feelings (including close friendship, romantic love or sexual attraction), between people. Examples of physical intimacy include being inside someone's personal space, holding hands, hugging, kissing, caressing and sexual activity. - The pun, also called paronomasia, is a form of word play that suggests two or more meanings, by exploiting multiple meanings of words, or of similar-sounding words, for an intended humorous or rhetorical effect. These ambiguities can arise from the intentional use of homophonic, homographic, metonymic, or figurative language. A pun differs from a malapropism in that a malapropism is an incorrect variation on a correct expression, while a pun involves expressions with multiple correct interpretations. Puns may be regarded as in-jokes or idiomatic constructions, as their usage and meaning are specific to a particular language and its culture. - Corporal punishment or physical punishment (physical discipline in some contexts) is a punishment intended to cause physical pain on a person. It is usually inflicted in settings with a substantial disparity of power between the partakers. - Sexual attraction is attraction on the basis of sexual desire or the quality of arousing such interest. Sexual attractiveness or sex appeal is an individual's ability to attract the sexual or erotic interest of another person, and is a factor in sexual selection or mate choice. The attraction can be to the physical or other qualities or traits of a person, or to such qualities in the context where they appear. The attraction may be to a person's aesthetics or movements or to their voice or smell, besides other factors. The attraction may be enhanced by a person's adornments, clothing, perfume or style. It can be influenced by individual genetic, psychological, or cultural factors, or to other, more amorphous qualities. Sexual attraction is also a response to another person that depends on a combination of the person possessing the traits and on the criteria of the person who is attracted. - A penis (plural "penises" or "penes" ) is the primary sexual organ that male animals use to inseminate sexually receptive mates (usually females and hermaphrodites respectively) during copulation. Such organs occur in many animals, both vertebrate and invertebrate, but males do not bear a penis in every animal species, and in those species in which the male does bear a so-called penis, the penes in the various species are not necessarily homologous. For example, the penis of a mammal is at most analogous to the penis of a male insect or barnacle. - Human bonding is the process of development of a close, interpersonal relationship. It most commonly takes place between family members or friends, but can also develop among groups, such as sporting teams and whenever people spend time together. Bonding is a mutual, interactive process, and is different from simple liking. - Apes (Hominoidea) are a branch of Old World tailless anthropoid primates native to Africa and Southeast Asia. They are the sister group of Old World monkeys, together forming the catarrhine clade. They are distinguished from other primates by a wider degree of freedom of motion at the shoulder joint as evolved by the influence of brachiation. There are two extant branches of the superfamily Hominoidea: the gibbons, or lesser apes; and the hominids, or great apes. - Muscle is a soft tissue found in most animals. Muscle cells contain protein filaments of actin and myosin that slide past one another, producing a contraction that changes both the length and the shape of the cell. Muscles function to produce force and motion. They are primarily responsible for maintaining and changing posture, locomotion, as well as movement of internal organs, such as the contraction of the heart and the movement of food through the digestive system via peristalsis. - The anus (from Latin "anus" meaning "ring", "circle") is an opening at the opposite end of an animal's digestive tract from the mouth. Its function is to control the expulsion of feces, unwanted semi-solid matter produced during digestion, which, depending on the type of animal, may include: matter which the animal cannot digest, such as bones; food material after all the nutrients have been extracted, for example cellulose or lignin; ingested matter which would be toxic if it remained in the digestive tract; and dead or excess gut bacteria and other endosymbionts. What is the relationship between 'sex swing' and 'sex toy'?
instance of