Nagini: If she's not a Horcrux, what the heck is she?

[justcarol67]

No: HPFGUIDX 171902

I notice that the vast majority of posters don't think that Nagini is
a Horcrux, possibly because they're sold on the Harry!Horcrux
hypothesis. Without getting back into that argument (I'll just say
that I think DD is right about Nagini and that if Harry or his scar
were a Horcrux, DD would have said so), I want to ask what people
think Nagini *is* (aside from being a "dirty great snake"). Is she
Voldemort's familiar? Just his ugly pet, who conveniently provides
venom when it's needed as a potion ingredient? How can he possess her
without doing lasting harm to her if she's not a Horcrux? Is she, erm,
a garbage disposal for the bodies of his victims? (LV offered her
Wormtail, retracted the offer, and offered her Harry. Perhaps she ate
Bertha Jorkins, whose body was never found?) Is Nagini evil in her own
right even though she's a snake, not a human being with free will, or
just too dangerous to live? (Surely, she can't be allowed to roam the
WW freely after LV is destroyed and I can't see her as an attraction
at the London Zoo.)

I think that, Horcrux or no Horcrux, Harry will slay her as he slew
the Basilisk, with the Sword of Gryffindor. Parseltongue will come in
handy as a diversionary tactic, and maybe Ron will be standing by with
some rue. (Okay, that last remark is facetious.)

Carol, who also wonders whether Quirrell smuggled Voldemort into
Britain while LV was possessing Nagini (and, if not, how did Q do it
since LV wasn't yet inside his head?)