So, apparently, in this new Tumblr version of the Hansen/Becket merfolks AU...
...Mermaid Jazmine grows scales on her body when she gets wet.
She thus no longer has female presenting mermaid nipples.
Why are only biologically female mermaids growing scales on their bodies, and not male ones?
Because, you see, among merfolks, mermaids are fierce warriors and hunters that protect their clan and typically go hunting for food. They thus require more protection to their upper bodies, and so their stomach and torso, in the ocean, are naturally covered by a chain-mail-like scales armor.
Since they thus have absolutely no exposed nipples under water, and their scales covered skin take longer to adjust to weight changes, you’ll be pleased to learn that it is only the biological males of the species that can get pregnant, carry the babies, and breastfeed them.
The scales only vanish on dry land, when they need to pass for humans. Otherwise, they have naturally stronger bodies and thicker skin than their biological male counterparts.
You can also bet that, in this AU, the merfolks are 100% non-sexist, egalitarian folks, that don’t see the female presenting nipples as sexual organs or features needing any type of covering, and they sure don’t bother with wearing shells or any sort of bras because “HEY! WATER! Natural support for titties! Why the fuck would I need a pair of shells? Jesus!”
So yeah, they don’t share the American culture at all in terms of the female presenting breasts being anything children should be protected from. That’s pure nonsense.
So that’s it! In this version, Jazmine gets scales whenever exposed to “wetness”. Yup!