Scorpio takes the genitals, the reproductive organs, the bladder and the excretory system. The modern reputation of the sign as the sexual one of the twelve derives largely from this assignment, and the derivation runs the wrong way round: the sign got the region because the region is where the sequence had reached, not because anybody had first decided the sign was sexual.
The older texts handle the territory with considerable reticence. Latin medical writing uses pudenda, the parts one is ashamed of, and secreta, and the surgical literature is generally more forthcoming about procedure than the astrological literature is about anatomy. What survives in the almanac tradition is mostly the prohibition rather than any description.
That reticence is itself part of the record. A reader coming to melothesia from modern popular astrology, where Scorpio's associations are stated at length and with enthusiasm, will find the sources thinner and drier than expected, and the elaboration a nineteenth and twentieth century development rather than a medieval inheritance.
The atlas records the historical assignment and its transmission. It makes no claim about reproductive or urinary function and offers no guidance of any kind.
Sources Divinity Atlas Long-Form Articles, First Edition with The History of the Term Pudendum: Opening the Discussion on Anatomical Sex InequalityAlexis Draper