 Sexual practices are commonly defined in Chinese as fangzhong shu or “arts of the bedroom” (Maspero 1981: 517–41). The large amount of literature existing on this subject shows that these arts are, with few exceptions, primarily addressed to males (another common term that defines them is yunü, “riding women”). Their main purpose is to avoid ejaculation: semen should be prevented from being emitted and should instead be “returned to the brain” (which is deemed to be the origin of the marrow, in its turn the source of semen). This method is known as huangjing bunao, “reverting the essence to replenish the brain”.