I believe I recall you posting information up about the story. So I do recall vaguely, as you had posted something up like a month or two ago. I want to say the parent was a human male(?)
Wikipedia does a better job of explaining why I'm classifying them as hermaphrodites. Specifically Slugs :
Quote:
Slugs are hermaphrodites, h
aving both female and male reproductive organs.[10] Once a slug has located a mate, they encircle each other and sperm is exchanged through their protruded genitalia. A few days later, the slugs lay around thirty eggs in a hole in the ground, or beneath the cover of an object such as a fallen log.
Apophallation is a commonly seen practice among many slugs. In apophallating species, the p***s curls like a corkscrew and during mating, it often becomes entangled in the mate's genitalia. Apophallation allows the slugs to separate themselves by one or both of the slugs chewing off the other's p***s.
Once its p***s has been removed, the slug is still able to mate using only the female parts of its reproductive system.[10]
But as a biology major with a heavy interest in zoology and genetics, I can assure you that scientifically this culture would be classified as a hermaphroditic species with variances in body types resulting from population stressors / adaptation. The difference basically being no more than a subspecies of a parent species that can still interbreed in most instances. They're basically proto-synapsids --- not quite reptile enough to be called a reptile but not quite a mammal either.
Hypothetically you could have an entirely non-mammary group reproduce within themselves without need of the ones with the ability to produce milk. Because you don't need the "male" and "female" ones together, you could have an entire population of one or the other without the two ever having to intermingle, which may eventually lead to such a genetic variance that they'd eventually be unable to interbreed to produce viable offspring. If anything that would also explain why there are individuals stuck ( in between ). It's basically a ring species under going a speciation event.
In humans men technically have breasts and mammary glands as well, it's just that due to the fact that they produce less estrogen, they don't develop. But individuals with both genitalia in our species are often the result of issues with chromosomes and so far have been sterile. It's not impossible to be genetically male, but have female genitalia --- as female is the human body's default. Funnily enough, it weren't for a very specific gene on the Y chromosome ( SRY ), men would be infertile females.
This link may actually help explain what I mean by ring species, by the way.
But hey - fantasy story - reality has little to no bearing. I.E. Your story has bathrooms, which didn't even exist in the Middle Ages as we currently know them. So it's pointless to really ask or dwell any further on it because ultimately you'll use your imagination and do whatever strikes your fancy. So you could have the pregnant character start shedding and changing color. Maybe even develop a territorial aggression. It's only limited to your imagination because it's not real.