Toward the end of chapter 16 the battle is in full force. Spider man and Sophie have just been killed along with David's father. Things are getting violent and pretty dire for the group of telepaths. At that moment the Sealand woman's thoughts break through. It's not loud and angry. It's not scared. It's clear and calm.
"The Sealand woman came in, calm, confidence-inspiring.
'Don't be frightened. We're coming. It's all right. Stay just where you are.'"
Moments later, the Sealand woman and her airship begin to arrive. It's like nothing anyone has ever seen before: a flying airship arriving in mist with spiderweb-like stuff descending on people. That could be terrifying, if the author changed a few descriptions around. If it was described as a dark, ominous mist with heavy rope-like chains, etc., that would be scary. Instead the entire sequence feels oddly calming and pretty.
"The mist made it indistinct in detail, but what I could see of it was just as I remembered: a white, glistening body with something half-invisible whizzing round above it. It was growing bigger and louder as it dropped to-wards us. As I looked down again I saw a few glistening threads, like cobwebs, drifting past the mouth of the cave. Then more and more of them, giving sudden gleams as they twisted in the air and caught the light."
It's light and airy. It's colored white, which is usually associated with purity, innocence, and good guys. It's the same in chapter 17 when David first sees the Sealand woman.
"Close in front of me, standing on the upper rungs of the ladder, and leaning inwards, was a figure entirely hidden in a shiny white suit. There were still filaments leisurely adrift in the air, but when they fell on the headpiece or shoulders of the white suit they did not stick. They slithered off and wafted gently on their downward way. I could see nothing of the suit's wearer but a pair of eyes looked at me through small, transparent windows. In a white-gloved hand was a metal bottle, with a fine spray hissing from it."
Notice all of the white: white suit, white gloved hand. Filaments are leisurely falling around her. All that's needed is slow motion and a wind machine to blow her hair gently around. Plus, she is calmly removing the painful threads from certain people. That' a very obvious sign of her kindness toward the group.
The Sealand woman then de-gloves herself and removes the hood from her head. David's entire group stands there dumbfounded at the shear beauty and perfection of her. I'll let the paragraphs speak for themselves.
"Her eyes were large, with irises more brown than green, and fringed with long, deep-gold lashes. Her nose was straight, but her nostrils curved with the perfection of a sculpture. Her mouth was, perhaps, a little wide; the chin beneath it was rounded, but not soft. Her hair was just a little darker than Rosalind's, and, astonishingly in a woman, it was short. Cut off nearly level with her jaw.
But more than anything it was the lightness of her face that made us stare. It was not pallor, it was simply fairness, like new cream, and with cheeks that might have been dusted with pink petals. There was scarcely a line in its smoothness, it seemed all new and perfect, as if neither wind nor rain had ever touched her. We found it hard to believe that any real, living person could look like that, so untouched, so unflawed.
For she was no girl in a first tender blossoming, unmistak-ably she was a woman — thirty, perhaps; one could not tell. She was sure of herself, with a serenity of confidence which made Rosalind's self-reliance seem almost bravado."
Notice that she is "perfect" and "unflawed." Even her skin's pallor is white and peaceful looking. There isn't a blemish on her. She is "serene" and "confident." She is everything that the Fringes and Waknuks are not. And she treats David and his group as if they are special in a very good way. THAT is very different from their treatment at home.