Oral sex is when you stimulate your partner's genitals with your mouth, lips or tongue.
This could involve sucking or licking their penis (also called fellatio), vagina, vulva or clitoris (cunnilingus), or anus (anilingus).
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Charles Alfred Kinsey, Kinsey Institute at Indiana University, dies. William Howell Masters, also fascinated with the science surrounding human sexuality, meets future research partner, Virginia Ellis Johnson, at Washington University in Missouri.
Avoid brushing your teeth or using dental floss shortly before giving oral sex as this could cause your gums to bleed.