Yes, where a demon is in you and you lose your soul. You become a demon because there is now a demon living inside you. They're a demon that can only exist with a mortal form to aid them but a demon none the less.
The body is just a shell. It explodes bc when dead things are held in arrested decomposition (like in permafrost) and are thawed, they rapidly decompose.
The demon is like a bodyless spirit that takes over a dead body. "You" are gone, the demon is using your corpse as transport.
Star Trek TNG also played with this theory in First Contact and Voyager, by depicting the Borg as zombies kept mobile by machinery.
So I mean they're demons with human shells? I think if you asked Joss Whedon about that I'm sure he'd corroborate. They only kinda fucked with the lore because they muddled the waters with Spike (given he had a big handicap) but otherwise all vampires are just demons with a human face and the memories of people you once loved. Supposedly they can love but without the human element it seems to just manifest as obsessive, confusing blood lust. Either way as far as Buffys concerned vampires are a form of demon and nobody ever treats or refers to it as a possession even when they gain their souls back. Once you're a vampire the demon and you are one and it's powers and hunger are still yours even if you regain morality.
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u/Miami_Mice2087 16d ago
"You die, and a demon sets up shop in your body." So it's sort of a post-mortem posession.