A ridge of tissue, known as the scrotal raphe or infrequently as the Vesling line, which is a universal feature of male genitalia. It runs the length of the scrotum and joins its counterparts, the penile raphe and the perineal raphe, to connect orifice to orifice. Its prominence varies from a cordlike stripe to undetectability between segments and people.
The peculiar part is that the line is a mystery of the male body. Even in our enlightened age, plenty of people aren't aware of having it or think they aren't supposed to. Sex ed focuses on the more functional bits, and info on the skin behind those is almost exclusively for women (with good reason. Things tend to tear in childbirth.) This node is dedicated to all the thirteen-year-old boys who find the thing and jump to Conclusions.
The scrotal raphe originates from the first trimester of pregnancy. The embryo doesn't develop the right genitalia immediately: instead it preps a distinctly feminine general-purpose template for the introduction of sex hormones. The release of testosterone and/or some worse-understood proteins causes it to become elaborate and decorated, or to close up for something else entirely. The latter forms a seam on the place where the prospective labia's halves meet and fuse. Rather like the last spike of the Transcontinental Railroad if Utah was your balls. Underneath it lurks the septum scroti, a wall of tissue that compartmentalizes the testes, presumably to keep the ducts and vessels involved from getting tangled.
Despite certain Conclusions, the scrotal raphe is not:
(the sound of feminists laughing in the distance)
However, it doesn't actually disprove any of the things it doesn't prove, does it? Enjoy!
The title and synyonyms were chosen after web searches to be optimal
search results. Also found was some semi-topical Star Wars fanfiction.
You people owe me.