I'm not sure how (or what) they are, but I have a theory... I think maybe the represent the earth, like Mother Nature incarnate type women. Think about it, they keep stuff like, 'I'm your mother, I'm everyone's mother." And they seem more concerned about the fate of the planet rather than the outcome of the "war" that's going on between the two main forces battling for the entire galaxy (it's been mentioned that earth itself is only like a "crumb" of the pie they're battling it out for control of.
(spoilers for Haunted Air)
I tell you, though, you just GOTTA love those people who show up only to give you vague-ass warnings about upcoming danger. Recall in THA Jack and Gia are about the to enter the house when one of them appears and says (and I'm paraphrasing here), "Don't go in there!" And they're like, "Why not?" and she basically replies, "Something bad will happen."
Oh wow, real specific there.
I mean, why didn't she just say, "Because the house is haunted by a little girl who wants to take your girlfriend's baby for her own." That would have taken what, all of three seconds?
I guess the only explanation I can think of is she didn't know
exactly what lurked in the house, only that it was something bad.
So, be wary of old ladies with dogs!