Deep Wizardry-wiz 2 by Diane Duane

circle—“
    Looking back, she wouldn’t have dreamed of it. The water was growing darker by the second, and as a result the glow of the krill in it was now visible —a delicate, shimmery, indefinite blue-green light that filled the sea everywhere. The light grew brighter, moment by moment; but it was brighter still at the surface, where the waves slid and shifted against one another in a glowing, undulating ceiling. And brightest of all was the track left by Aroooon’s swimming—a wake that burned like clouds of cool fire behind him with every slow stroke of his tail.
    At the head of the wake, Aroooon himself traced the grand curves of his spell, sheathed in bubbles and cold light. One circle he completed, melding into itself as he sang that single compelling note; then he began another at right angles to the first, and the water burned behind him, the current not taking the brilliance away. And the blue’s song seemed to get into the blood, into the bone, and would not be shaken—
    “HNii’t,” S’reee said, “we can’t stay, you said you have to get back—“
    Nita looked around her in shock. “S’reee, when did it get so dark! My folks are gonna have a fit!”
    “Didn’t I mention that time didn’t run the same way below the water as it does in the Above?”
    “Yeah, but I thought—“ Kit said, and then he broke off and said a very bad word in whale. “No, I didn’t think. I assumed that it’d go slower—“
    “It goes faster,” Nita moaned. “Kit, how are we going to get anything done? S’reee, how long exactly is the Song going to take?”
    “Not long,” the humpback said, sounding a bit puzzled by her distress. “A couple of lights, as it’s reckoned in the Above—“
    “Two days!”
    “We’re in trouble,” Kit said.
    “That’s exactly what we’re in. S’reee, let’s put our tails into it! Even if we were getting home right now, we’d have some explaining to do.”
    She turned and swam in the direction where her sharpening whale-senses told her home was. It was going to be bad enough, having to climb out of this splendid, strong, graceful body and put her own back on again. But Dairine was waiting to give her the Spanish Inquisition when she got home. And her mother and father were going to give her more of those strange looks. Worse ... there would be questions asked, she knew it. Her folks might even call Kit’s family if they got worried enough—and Kit’s dad, who was terminally protective of his son, might make Kit come home.
    That thought was worst of all.
    They went home. It was lucky for them that Nita’s father was too tired from his fishing—which had been successful—to make much noise about their lateness. Her mother was cleaning fish in the kitchen, too annoyed at the smelly work to much care about anything else. And as for Dairine, she was buried so deep in a copy of The Space Shuttle Operators’ Manual that all she did when Nita passed her room was glance up for a second, then dive back into her reading. Even so, there was no feeling of relief when Nita shut the door to her room and got under the covers; just an uneasy sense of something incomplete, something that was going to come up again later … and not in a way she’d like.
    “Wizardry ...” she muttered sourly, and fell asleep.
    Ed’s Song
    “Neets,” her mother said from where she stood at the sink, her back turned. “Got a few minutes?”
    Nita looked up from her breakfast. “What’s up?”
    Her mother was silent for a second, as if wondering how to broach whatever she had on her mind. “You and Kit’ve been out a lot lately,” she said at last. “Dad and I hardly ever seem to see you.”
    “I thought Dad said it’d be fun to have Dairine and me out of his hair for a while, this vacation,” said Nita.
    “Out of his hair, yes. Not out of his life. —We worry about you two when you’re out so much.”
    “Mom, we’re fine.”
    “Well, I wonder... What exactly are you two doing