The oldest Lilim lives with her two sisters in a cottage in the woods. It's a dreary existence—"They took it in turns to sleep in the big bed, to make the supper, to set snares in the wood for small animals, to draw water up from the deep well behind the house" (3.54)—at least, it is until they divine from the entrails of a dead stoat that a star has fallen to earth. Now life is exciting as all get out as they scramble to get to her first.
Since the oldest wins the animal-organ lottery, she gets to use up the last of their youth and go out to seek the star. She is transformed into "a tall, handsome woman with black hair and dark eyes and red, red lips" (3.88). She sets out, enchanting a boy into a goat to help draw her small cart as she travels Faerie to seek the star.
She is cruel, but also fair, so when Madame Semele extracts a promise not to harm her, the witch-queen must obey it. She curses Madame Semele to never be able to sense the star, no matter how close she is to it, though, which is a pretty decent punishment considering how much Madame Semele wants to restore her youth too. And the witch-queen also lets her know what she would've done but for the oath, saying:
"Had I not so sworn I would change you into a black-beetle, and I would pull your legs off, one by one, and leave you for the birds to find." (5.87)
Yep. Definitely not nice, and definitely good this lady is bound to keep her word.
The more magic the witch-queen uses, the older she gets. So after transforming her chariot into an inn, and supplying an innkeeper and daughter from goats, "There were streaks of grey now in her raven-black hair, and dark pouches beneath her eyes" (6.61). She's got powerful magic, but it comes at a very real cost to her.
Still, she convincingly manages to play the part of a sweet middle-aged woman, coaxing the star to enter the inn to warm up and dry off: "'Look at you, wet as a water-nixie, look at the puddle under you, and your lovely dress, oh the state of it, you must be soaked to the bone'" (7.12). She comes across as pretty harmless here, right? Not like someone planning to cut out your heart at all.
After the debacle at the inn, though, she ages quite a bit: "Her hair was mostly grey, now, and her face was pouched, and wrinkled at the throat and eyes and at the corners of the mouth" (8.45). By the time she meets up with Septimus, she looks really old, even aging as he watches, having worked magic to keep him from burning down her hut. She works with what she's got, though, so she paints herself as a helpless victim, telling the dying man:
"You should be ashamed of yourself […] Attempting arson and violence upon the person of a poor old lady living on her own, who would be entirely at the mercy of every passing vagabond, were it not for the kindness of her little friends." (9.18)
The "little friend" in this instance just so happens to be her snake bracelet… which magically comes alive and kills Septimus with its poison. That is one handy little friend, if you ask us.
The witch-queen's age creeps up on her, but then, she was pretty old to begin with. When she dines with Madame Semele, she introduces herself as "Morwanneg" as a joke, "for Morwanneg means wave of the sea, and her true name was long since drowned and lost beneath the cold ocean" (5.69). And then when Madame Semele asks who she really is, the witch-queen replies:
"When you knew me last […] I ruled with my sisters in Carnadine, before it was lost." (5.89)
We've never heard of Carnadine but we're guessing it's something super ancient like Atlantis since it's been lost and she says her name has sunk into the depths of the ocean.
By the time Madame Semele pulls up to Diggory's Dyke on the way to the Faerie Market, the witch-queen is unrecognizably aged: "The woman's hair was white as snow, her skin was wrinkled, and one eye was blind" (9.25). And when she reaches the Faerie Market, she is "shrunk by age and time to little bigger than a child" (10.195). Yvaine doesn't recognize her, even after the old woman calls her over to talk.
The witch can't figure out what happened to the star's heart, saying, "'Not long ago you burned—your heart burned—in my mind like silver fire. But after that night in the inn it became patchy and dim, and now it is not there at all'" (10.201). What the witch-queen missed is that Yvaine has fallen in love and essentially given her heart to Tristran. When Yvaine points this out, the witch-queen says what a bad idea this is:
"You should have let me take it back then, for my sisters and me […] Your boy will break it, or waste it, or lose it. They all do." (10.207)
This, unfortunately, is what the witch-queen's world boils down to: Hearts are meant to bestow power, not to be wasted in love. She goes back to her sisters, who will undoubtedly punish her for using up the last of their hoarded youth and not coming back with the star after all. Do we pity her? Yvaine does, but we're not sure if we're that kind or forgiving.
The witch-queen won't live forever to keep abusing her power. She tells Madame Semele:
"They have said that the Lilim were dead before now, but they have always lied. The squirrel has not yet found the acorn that will grow into the oak that will be cut to form the cradle of the babe who will grow to slay me." (5.91)
Since she says this while under the influence of an herb that forces her to speak the truth, it will come true, and at the end of this section, we see a squirrel finding an acorn, and then running off to bury it. In other words, all good (and bad) things come to an end, even the Lilim.