Water was the first enemy.

Zheyu had assumed it would be simple. He had watched Qinghe wash her face the previous morning, a quick scoop of the hands, a splash, a rub with a cloth, and she had made it look like nothing. But when he stood alone in the inn's small back courtyard in the grey before sunrise, bent over a stone basin with his sleeves rolled to the elbow, he discovered that cold water on a living face was a matter of real violence.

He yelped.

It echoed off the walls. A startled sparrow went up from the wellhead. Zheyu stood with both hands over his mouth, dripping, his heart hammering, and listened for any sign that the house had woken.

Nothing. Only the soft slap of the canal against the quay, and the dull far-off call of a ferryman.

He lowered his hands and looked at them. They were shaking, a little, and he was smiling. He could not seem to help it. The cold had gone straight through his skin and into the bones of his face, a clean, bright, merciless sensation, and he had felt every drop. He had forgotten that a body could be shocked into wakefulness. In the sword there was no morning. There was only the long dim sleep, and then the sudden light.

He bent and tried again, more slowly. Palms together, a scoop, a breath. It was not so terrible the second time. By the third he was almost enjoying himself.

Fire next, he thought. Qinghe had promised him this the night before, in the tone of a woman describing a punishment. You can make yourself useful in the mornings. He had taken it as the greatest compliment of his life.

The kitchen hearth stood at the far end of the yard under a lean-to roof, a squat brick oven with a blackened iron pot and a basket of kindling beside it. Zheyu crouched in front of it. He knew the theory of fire. He had been present at the making of Qingming, after all, and a forge was only a very large and very ill-tempered hearth. He had watched a great many fires from within a sword. But there was a gap between knowing and doing, and his hands, which were long and clever in theory, turned out to be remarkably stupid in practice.

He built a pyramid of twigs. It collapsed. He built another. He struck the flint, and a spark flew, and died on the cold iron. He struck it again and nearly took off the end of his thumb. He tried blowing on the kindling, and a puff of ash rose and settled gently on his nose.

By the time the sky had turned from grey to pearl, the hearth held a heap of smouldering twigs, a scorched sleeve, a great deal of smoke, and one very discouraged ghost.

"You're doing it wrong," said a voice behind him.

He did not jump. He had learned already to feel her coming, a certain pressure at the back of his neck, the tug of the thread drawing taut and slack. But he turned his head too quickly and a bit of ash got into his eye, and he said, "Ah," and put the heel of his hand to it.

Qinghe stood in the doorway of the kitchen with her arms folded. She was still in her sleeping robe, a plain grey thing, and her hair hung loose over one shoulder in a long dark rope. She had not yet tied it up. He found that he could not look at her directly. It was too much, somehow, the loose hair and the sleep-creased cheek and the bare feet on the cold stone.

"I am learning," he said.

"You're burning down an inn."

"It is a very small fire."

"It's a very small smoke. There's no fire." She came across the yard. She did not hurry, and she did not look at him. She crouched beside the hearth and with two quick, impatient motions swept the ruined pyramid apart. "Dry wood first. Thin shavings at the bottom. You don't pile it, you let the air through. It's like a lung."

"A lung."

"It needs to breathe. Hand me the flint."

He gave her the flint. Their fingers did not touch. He was careful of that.

She struck once, a short glancing blow, and a spark leaped into the shavings and caught. A tiny orange tongue curled up and began to eat. She fed it, twig by twig, with the economy of a woman who had done this on a thousand cold mornings, until the little fire had grown into a clean, crackling blaze, and then she sat back on her heels and wiped her hands on her robe.

"There," she said. "Like that."

"It is beautiful," said Zheyu, quite honestly.

"It's a fire."

"I know. But I have never made one. I have been near a great many, but I have never made one." He watched the flames. "It is a different thing to be the one who started it."

She was silent for a moment, and when she spoke her voice had changed. It had lost a little of its edge. "Master Ye used to say the first thing a swordsman learns is how to keep warm. He said a cold hand can't hold a blade, and a hungry stomach can't hold a thought. Fire, then food, then forms." She poked at the coals with a stick. "He said the rest was just ornament."

"He sounds a practical man."

"He was."

"Did you love him?"

The stick stopped moving. Zheyu felt the question land, and he thought, Too soon, you fool, and opened his mouth to withdraw it. But she said, very low, without looking up, "I don't know. I think I was grateful. I think that's the same thing, for some people."

"It is not the same," he said gently. "But it is close kin."

She looked at him then, quick and sidelong, the look of someone checking whether she had been mocked. She found nothing there but a quiet attention, and her shoulders eased by a hair's breadth.

"Put the water on," she said gruffly. "The pot's on the hook. I'll find us something to eat."

* * *

They ate on the back step in the first thin warmth of the sun, with the canal gleaming below them and the willows moving gently in the breeze. Mei had left a covered dish on the kitchen table, pickled radish and cold sliced egg and thick rice porridge, and a note in an untidy scrawl that said Eat, you are both too thin. M. Zheyu had read it twice. He could read, of course, though the characters had changed over the centuries and he had to puzzle out some of them. Qinghe had read it once and made a noise like a cat being stroked the wrong way.

"She likes us," Zheyu offered.

"She likes making trouble."

"Those need not be different things."

Qinghe snorted into her bowl. It was, he thought, very nearly a laugh.

They sat in silence for a while, and it was an easy silence, which surprised him. He had expected it to chafe. In the sword he had been so long alone that conversation had become a thing like a bridge, rickety and requiring constant attention, and he was always waiting for the plank to give way. But with her there was only the clink of spoons and the cries of the boatmen and the sound of her chewing, which he found, absurdly, he liked.

Careful, said a small wary voice at the back of his mind.

He ate his radish. It was sour and crisp and made his eyes water.

"Tell me about the others," said Qinghe.

He nearly dropped the bowl.

She had spoken without looking at him, her gaze fixed on the water. Her tone was flat, practical, the tone of a woman who wanted information, and that was exactly why it caught him unprepared. "The others," he repeated.

"The ones before me. You said there were more than two. I'd like to know what I'm dealing with."

"I told you. I do not remember all of it."

"Tell me what you do remember." She set her bowl down on the step. "I'm not asking for secrets. I want to know what kind of people held that sword. What they wanted from it. If they," she hesitated, and he saw her jaw tighten, "if they hurt you."

It was not what he had expected. He turned the question over and found, rather to his own astonishment, that he wanted to answer it.

"There was a woman," he said slowly. "Very tall. Broad in the shoulder, with a voice like a bell. She hummed when she walked, always the same four notes, and when she was angry she hummed lower. She carried me for, I think, eleven years. She was a ferrywoman before she was a swordswoman. She used to let me out at night and sit by the river, and she would tell me the names of the stars." He smiled faintly. "She got them wrong. I never told her."

Qinghe's eyes had come around to him.

"There was a man who stammered. Very thin. His hands were always cold, even in summer, and he held me as if I might bite. He apologised to me whenever he drew me. Excuse me. Sorry. Forgive me. As if the steel could be offended." He paused. "And a boy. A laughing, ridiculous boy, who called me old friend and used to leave sweets on the hilt. I did not need sweets. I could not eat them. But it was kind."

"And then?"

"And then what?"

"What happened to them?"

He opened his mouth. He reached for the end of the thread, as he had done in the valley, reached for the final scene in each of those lives, the last night, the last hand, the last time he had been put down or taken up. And there was the wall again. Smooth. Blank. A pane of dark glass, and nothing behind it.

"I do not know," he said. His voice had gone small. "I remember them as they were. Alive, and kind, and talking. I remember the first day, and the middle days. But the ends, I cannot see. It is as though someone has drawn a curtain across the last page of each book."

A cold unease crept up his spine. He had known this for a long time, of course, in the dim way you know a stone is in your shoe. But he had never put it into words, not to anyone. Spoken aloud, in the clear morning, it sounded very strange. And very wrong.

"Someone drew it," Qinghe said quietly. "Or something."

"Perhaps."

"Does it frighten you?"

"Yes." He did not dress it up. "It frightens me a great deal. I think I am afraid of what is behind it."

She was quiet. Then, to his astonishment, she reached over and nudged his bowl a little closer to his knee with the side of her hand, a small, brusque, wordless gesture, the kind one makes toward a person who has gone pale and has forgotten to eat.

"Finish that," she said. "It's getting cold."

He finished it.

* * *

It was a long, mild, golden day. She took him with her to the market, and he walked behind her through the tangle of stalls with his hands tucked into his sleeves, saying nothing, as instructed, and failing to look anything but entranced. She bought rope and oilcloth and a whetstone and a bag of dried plums. She haggled with a woman over a bundle of needles and won. She stopped at a stall that sold ribbons, and her hand went out for a moment toward a length of pale blue silk, and then drew back as if it had been burned.

"You like the blue," said Zheyu.

"I don't need it."

"I did not say you did."

"I've a ribbon already." She touched her crown with two fingers. The ribbon was there, faded and soft at the edges, tied in a firm practical knot. "It was a gift."

"From Master Ye?"

"From a student who left." She shrugged, a small, hard movement. "A long time ago."

He wanted to ask more. He did not. He stood beside her at the ribbon stall in the dappled shade of a willow and watched the lines of her face, and thought that he had never in all his years known anyone so careful about what they would let themselves want.

She has a rule, he thought. A rule for everything. Do not draw to frighten. Do not owe. Do not need. And then, with sudden, cold clarity: And you are the first thing she has not been able to put a rule around.

He did not say it. It was not his to say.

But he felt, in that small bright moment, a slow and dangerous tenderness spreading through his chest like warmth through a cold limb, and it was so unfamiliar that he did not at first recognise it.

* * *

On the way back they crossed the second bridge, and a small voice stopped them.

"Mister! Mister scholar! Please!"

A girl of perhaps seven stood at the foot of the arch with her fists clenched at her sides and her face blotched red from crying. Above her, snagged high in the branches of a willow that leaned over the water, hung a paper kite shaped like a carp, its long painted tail fluttering. The string trailed down, tangled in the lower twigs.

"It's my brother's," she said, hiccuping. "He'll hit me if I lose it. Please, can you reach?"

Zheyu looked at Qinghe. It was an anxious, asking look, the look of a man who had been given three rules and was afraid of breaking the second.

"Go on," she said, exasperated. "It's a kite, not a state secret."

He went. He climbed the bank in two long strides, and she watched him study the branch, tilting his head, and then, rather than reaching for the kite, lay his palm flat against the bark of the willow and stand quite still. A breath of wind rose off the water. The branches swayed, gently, apart, and the carp slid free of its twig and sank into his hands as softly as a leaf.

He turned and presented it to the child with a small bow.

"It was not hurt," he said gravely. "Only frightened. You should tell your brother it has been on an adventure."

The girl stared up at him. Then she snatched the kite, clutched it to her chest, and ran, calling over her shoulder in a high, wobbling voice, "Thank you, mister!" He stood looking after her with his hands open, and an expression so tender and so naked that Qinghe looked away.

"You didn't climb," she said when he rejoined her.

"I asked the tree."

"Trees don't answer."

"This one was very obliging." He walked beside her again, and for a few paces neither spoke. "It is an old trick. Everything that grows near a blossoming peach wakes a little, in the season. The willows especially. They are fond of company." He glanced at her. "You did not seem alarmed."

"I've seen stranger this week."

"I suppose you have."

"That wasn't a trick of the blade?"

"No. Only a trick of me." A pause. "I am sorry. Was it wrong to do it?"

She thought about the way he had said it was only frightened, and the way the child's tears had stopped, and the way the whole bridge seemed to have grown a little gentler for his having stood on it.

"No," Qinghe said, to the water. "It wasn't wrong."

* * *

That evening, back at the inn, she sat on the edge of her bed and began to clean the sword.

She did it every night. He had noticed that. Oil, a soft cloth, the long slow stroke from guard to tip. She did not do it as a chore. She did it as other people prayed, with her head bent and her whole attention gathered into the small circle of her hands. When she reached the hilt, her thumb found the black cord below the guard and began to move over it, back and forth, back and forth, in a small absent rhythm.

He had seen her do it three times now. It always happened when she was thinking about something she did not want to think about.

"Your thumb," he said.

She stopped. "What?"

"You do that when you are troubled. You rub the hilt. Just there." He nodded at it. "I can feel it. Every time."

She looked down at her own hand as if it belonged to a stranger. Then up at him, startled and accusing, and he realised too late that he had said something he should not.

"You can feel that?"

"A little. The hilt is the oldest part of me." He gave a small, rueful shrug. "It is not unpleasant. It is rather," he searched for the word, "like being petted."

The silence stretched.

"Don't," she said at last, carefully, "tell me things like that."

"I will not do it again."

"You'll say that and then you will."

"Probably," Zheyu admitted.

She gave a short, breathless huff, not quite a laugh, and went back to her cloth. But she did not touch the cord again. He saw her put her thumb flat against the scabbard instead, away from the hilt, and hold it there, stiff and still, as if she were trying very hard not to feel anything at all.

He lay down on his bed, behind the heron screen, and turned his face toward the wall.

The lamp burned low. Beyond the screen she was moving about, folding her robe, setting the sword on the floor, and every small sound reached him with an extraordinary clarity. He heard the creak of her mattress. He heard her breath, which was not quite even. He heard the faint rasp of her hair as she turned her head on the pillow.

He realised that his right hand was curled into a fist on the blanket.

He did not know when it had happened. His knuckles were white. Every muscle in his forearm was tight, and the nails had bitten into his palm, and he could not account for it, until he understood with a slow, stunned horror what the hand had been about to do.

It had wanted to reach through the screen. Just that. To find her hand in the dark and hold it. To lay his own over hers and say nothing at all.

He stared at the ceiling and made himself unclench, finger by finger.

Stop, he told himself. Stop it. This is the binding. You know how it works. You are tied to her, and the tie makes you want what it makes you want. It was the same with the ferrywoman. It was the same with the boy. A weeks-old fondness, born of proximity and need. It is not real.

Is it not?

He lay very still. Outside, a boat went by, and its lantern threw a long wavering gold across the ceiling and was gone.

He did not know. That was the terrible part. He had lived three hundred years in the dark and he had never once been able to tell where the thread ended and he began. Was the warmth in his chest his own? Was the ache a feeling, or a leash drawn tight? When she walked away, and the pain came, was he afraid of dying or only afraid of being alone?

If I loved her, he thought, I could not know it. I could never know it.

And it would be the cruellest thing he had ever done to her, to let her believe it was real.

Behind the screen, she turned over in her sleep, and murmured something, a single indistinct syllable that might have been his name.

Zheyu shut his eyes, and did not sleep.