The Changeover by Margaret Mahy

tears a strip off you for entertaining older seventh form men in your pajamas."
    "You really do think you're terrific, don't you?" Laura said with a faint grin.
    "Someone has to," Sorry replied, following her into Jacko's room. "Those harridans at home have been... Heavens above, Chant!" he suddenly exclaimed. "What's that smell?" Laura could almost have hugged him because he could smell the peppermint too, but she held her breath and waited while he looked at Jacko.
    "Well, well!" he said after a moment. "You clever girl! You were right and I was wrong." Laura released a gushing sigh of relief. Sorry sat down on a chair by Jacko's bed — a chair draped in Kate's underwear.
    "Go on! Tell me all!" he said, as he lifted first one of Jacko's eyelids and then the other, not so much to look at his eyes as to notice the way they closed. Laura told her story as tersely as she could.
    "Demon! Spirit! Incubus!" said Sorry. "It sounds to me as if whatever faculty you have that makes you — you know — able to guess at some of the extreme people drifting around in the world — it sounds as if that faculty was stuck for the right word. Does this Carmody Braque have any — did he have a word branded on his forehead, say, or any mark that might have been a word crossed out?"
    "No, nothing like that," Laura said definitely. "He was quite bald — his hair was thin and clipped very short. I'd have certainly seen it." Sorry appeared to abandon a briefly-held hypothesis of his own. He stared at Jacko — picked up his hand and sighed, shaking his head.
    "Have you ever heard of the lemures?" he asked at last.
    "Monkeys?" Laura said.
    "Primates!" said Sorry absentmindedly. "No— not those. The lemures were the wicked spirits of the dead ... the lavae or lemures. I don't think your Carmody Braque is actually an incubus. I think he's a wicked spirit that has managed to win a body for itself once more and has probably gone on by absorbing the lives of others — their energy — to keep himself alive. You were almost right when you said he was a vampire, but it's not mere blood he's after. It's the essence of life itself." He looked at Jacko as if he were some sort of a rare flower whose stem had been bent by a storm. "The fact is ..." he said after a moment, and then grew silent. "You're a big, brave girl, Chant, aren't you ... the fact is I think your little brother has had it."
    "You mean you think he might be going to die?" Laura cried, hearing her voice high and hard in the dim room.
    "He's sealing up," Sorry said in his light, remote way. "Even if I had come last night there's nothing I can think of that I could have done about it." Laura began to feel very cold— as cold perhaps as Jacko lying in his blankets but not warmed by them.
    "You really think he's going to die?" she repeated.
    "He's sealing up." Sorry also repeated himself in a reasonable voice as if stating a fact she must accept. He looked quite lighthearted, interested in the problem but not affected by it. "Sealing will help for a while, I suppose. It's a form of hibernation — aestivation really ..."
    "I don't want a lecture," Laura said, staring at him incredulously, for he sounded like a teacher at school.
    "You really think he's going to die?"
    "You asked me that a moment ago. I'm sorry," Sorry said and shrugged. "I shouldn't think he'd stand out for very long against this sort of possession. Well, it's not so much a possession as a consumption."
    "Come into the tidy room," Laura said after a moment. "You could have a glass of symbolic sherry."
    "At nine-fifteen in the morning?" Sorry asked, "and on an empty stomach?" He followed her out and sat down opposite her at the table. Laura lifted her eyes to his and looked at him steadily, and his grey eyes went blank and then shifted away from hers, turning silver in the oblique light from the window.
    "You upset, Chant?" he said in a careful voice.
    "He's my brother, and I love him, and you say he's going to die," Laura