I honestly rlly like confed as a character, idk just there complex relationship with ame and goofy yet hauntingly sinister personality just makes for such a cool character to me. Btw these ghosts aren't technically named ghosts, there called doppelgangers but they can also be called ghosts. For now I'll call them ghosts but just know there more official name is a doppelganger.
Now first...

HOW TF DO GHOSTS EVEN EXIST??
Ghosts in my au are actually rlly interesting, ghosts are the embodiment  of fear and torture from a countryhumans early life. They kinda just appear out of nowhere. When the countryhuman and ghost are children the ghost actually doesn't speak much if at all.
this could be because some ghosts develop slower than others, maybe there out right afraid of there twin or other countryhumans, or they don't have the ability to speak or hear when there younger take ya pick-
Ghosts as they get older with there twin normally start to interact with them more but also persuade them more or atleast try. Ghosts are normally more blunt and have there priorities set and it's hard to change that most of the time.
Ghosts normally actually want the best for there twin and exist for that matter, there are only few who outright want to get rid of there twin... the thing is ghosts have slightly demented or bent morality which backfires them most of the time.

Ok now,
HOW DO GHOSTS ANATOMY EVEN WORK?
Ok this might seem like a pretty weird and straight forward one but not actually.
Ghosts biologically are actually all non binary, sure they can go by he him or she her pronouns but biologically there all non binary bois. The reason for this is because to me I don't get why a ghost would need a gender, like- do they reproduce? No? So why would they need a gender if it has no purpose? So yeah there all non binary but they can go by he/him or she/her pronouns if they like.
There voices are also more high pitched or weird like. Confed has this high pitched slightly broken and glitchy voice but some others have a voice that sounds like three people are talking. Maybe there voice echos. Maybe it replicates the voice of another in a more demented way you get it. The reason for this is first, well being mute for nearly all your childhood is of course gonna do something to your voice:/ next since there ghosts I think there voice box in general would just be a bit more broken since there not technically alive. Like I'm not saying there on the brink of death every second but they are definitely less attacked to reality well- they have a very different perspective of reality.

Ok also yes in my au ghosts can possess there twin but they can also detach from them, for a ghost to posses there twin there twin has to allow them too but for them to detach they have to while there twins body is more weak like maybe they have wounds or are very ill.
The reason is because if the body is weaker it can't fight back so much to there splitting. But this does have a downside, a countryhumans body can only survive detaching from there twin once, if there twin ghost dies and they become well, a ghost again they can never detach again, only posses.
This is because detaching makes the body extremely weak and if they were ever to do that again there is a very big likely hood both the twins would die.
Although a ghost can posses there twin forcefully while there in a weak state and not die due to possessing being less dangerous than detaching.
The only way a ghost can really die is by being killed by there twin. just giving up since unlike countryhumans ghosts can kinda just give up and fade away on command, since again there less attached to reality in a weird way. And if there twin starts fading, ok let me explain this.
If a ghosts twin starts fading the ghost will also start fading. The thing is in certain circumstances a twin can survive fading or have it stop in some way but that won't happen to the ghost. The ghost will fade away completely.

Some ghosts in my au are confed, third Reich, martial law and some others.
Yeah this is a lot-