Demon-Slaughtering Cave
by katzenfabrik

Demon-Slaughtering Cave

katzenfabrik

Summary

Xue Yang is apprenticing in demonic cultivation in the Burial Mounds; Wen Qing is trying to keep Wei Wuxian's body and soul together; Wei Wuxian is pretending that everything is all right when it clearly isn't. They all need to blow off a little steam.

Notes

None
Imported from Archive of Our Own. Original work id: 29747004.

Chapter 1

Darkness had swelled and covered the Burial Mounds—the mundane darkness of night, obscuring the mist-veil of resentful energy that dimmed its skies all the time. What was left of Wen Qing's clan had retreated to bed not long after sunset. They didn't have the lamp oil to waste on defying nature's rhythms.

Cool, damp air streamed into the Demon-Slaughtering Cave, summoned in by the heat haze over the dozen or so candles burning on ledges around the central chamber. Now that the winter was well and truly over, it was a welcome relief. Wei Wuxian, a man whose life was dedicated to defying nature, and Wen Qing, a woman who had never believed in sleeping when she could have been working, were still awake.

"Keep your head still," she told him through her teeth. The needle she'd been about to push into his forehead wavered in midair.

"Just a moment, just a moment," he protested, wriggling with his whole body as one arm stretched out to search for the writing materials on the floor by his improvised bed. "Let me write this thought down. It could be instrumental for clearing land for farming—"

"I said, hold still." Wen Qing pushed down on his shoulders and leant her whole bodyweight on them, quite aware that he only stopped moving as a courtesy to her. "You are not supposed to be having thoughts, you are supposed to be letting me attempt to balance your meridians. Temporarily."

"Qing jie..." Wei Wuxian began, with a whine in his voice.

"Furthermore, I've already told you that there's no way I'll let you raise the bodies and make them walk out of the soil by themselves."

He let his hand flop down onto the straw and rags. "Even if—"

"Yes, even then."

Wen Qing straightened up. She moved the little sesame-oil lamp off the stone platform, in case he rolled over and knocked into it, and then paced in a slow circle, rubbing her lower back. The cave walls were drifted up with discarded drawings and half-finished talismans. If all you have is blasphemous, soul-destroying cultivation, she supposed, everything looks like a corpse. That was a little too dark for her to say out loud, even in this half-lit time out of time. It wasn't as though she didn't see Wei Wuxian every single day up here in exile, often too much of him, in all his wildly varying moods, but these late nights when they were the only ones awake still felt different. She'd told him things on nights like these that she wouldn't have said even to A-Ning.

When she turned back to the rock he was using as a bed, Wei Wuxian was lying back with one knee up, staring vacantly at the cave roof.

"Are you going to behave properly and let me work now?" she asked. "Or am I really going to have to hold you down?"

A low whistle echoed through the cave, splitting open their private bubble. "Stop me if I'm interrupting anything," drawled Xue Yang as he rounded the bend. At the sight of Wei Wuxian, supine and shirtless, his eyes widened. "Am I interrupting?" he asked.

Wen Qing resisted the urge to draw her robes more fully closed and tighten her sash. She was dressed with absolute propriety, she knew. So was Wei Wuxian, as her patient. It was just the shivery feeling that little delinquent gave her, the conviction that his gaze wasn't restricted to straight lines but could shimmy into her neckline if he wanted it to.

"A medical treatment only," she replied in clipped tones, forcing herself to look at her patient instead of the intruder. Still lost in thought, he hadn't acknowledged Xue Yang's entrance at all. "Wei Wuxian." She raised one hand as if to slap his cheek. "Your apprentice is here. Do you want him to leave?"

"What? Oh, Xue Yang." He pushed himself up onto his elbows, face suddenly animated again. "No surprise you can't sleep either. He can stay, Wen Qing. Might as well get a foretaste of what will happen to him if he keeps up the demonic cultivation!"

"Pfft, as if I'm going to let myself go like you, old man," Xue Yang said, but only after a pause, and without feeling in his voice. His eyes were fixed on Wei Wuxian's chest.

Wen Qing rolled her eyes and tapped on both his shoulders. "Down."

"If Wen daifu needs someone to hold him down..." Without her realising, Xue Yang had sidled up behind her. She swallowed so that her voice wouldn't crack.

"Get on the other side of the bed. If he tries to innovate an entirely new school of cultivation again, please restrain him all you like." Well. That had come out coolly enough, but she should have left off the last few words. Xue Yang's eyes flashed as he took up a position opposite her, her patient between them.

"Qing jie is so cruel to me," Wei Wuxian said, but held obediently still as she fished her needles out of her robe and began to work again. She noted that his breaths came faster and shallower than they had before.

Normally she preferred to work in silence, but she found herself explaining the process as she worked, the same way she would have spoken to A-Ning. Wei Wuxian ought to know all of this, the number of times she'd lectured him on the damage he was doing to himself; in fact, he could probably have led a class on the topic. Would that stop him practising demonic cultivation? No—and they both knew, though she hated to admit it, that their little colony couldn't afford for him to stop.

To Xue Yang, on the other hand, this seemed to be entirely new information. He interrupted far more frequently than A-Ning would have—which was to say, at all—and his questions were often non sequiturs and phrased as demands, but she could tell that every word she said lodged somewhere behind those glinting black eyes.

It was one of those questions that tipped her tight control over the situation suddenly out of her hands.

As she slid the latest needle under the skin over Wei Wuxian's sternum, he hissed sharply. There was a wrinkle between his eyebrows, and she watched with what she thought was private satisfaction as his nipples stiffened to stand proud of his chest.

"Does it hurt?" Xue Yang asked hungrily—

—and she said, before she could stop herself, "Oh, it can," and flicked the end of the needle.

Wei Wuxian let out a groan that did something entirely non-medical to her. The Demon-Slaughtering Cave seemed to spin around her briefly, as the blood in her body shifted downwards.

Across the bed, Xue Yang was holding his breath. His eyes flicked up to her face and back down immediately, as if he hoped Wen Qing would forget that he was there. Wei Wuxian, on the other hand, was looking directly at her. When she met his gaze, he held it as if nothing else existed around them. As she watched, his eyes grew darker.

Moving very deliberately, reaching for her lapel, she said into the flame-flickering silence, "I hope you understand, Xue Yang, that these needles are strictly medical tools." The boy made the start of a noise but she held up one hand and he stilled immediately. She pulled the other roll of needles out from her robe. "These, on the other hand, are not."

Something seemed to relax on Wei Wuxian's face. His lips parted. She'd seen it before, that expression. Funny that she'd never expected to see it on him, because now it seemed as though his face had been designed for it.

"Xue Yang, hold his shoulders," she said, and the boy jumped to obey. His hands trembled against Wei Wuxian's skin. "Good boy," she told him. "You can press harder. Yes, like that."

"Who says I'm a good boy?" he muttered darkly.

"If I tell you to be a good boy, then you will be one."

She was aware of something passing between the other two, something she didn't feel the need to control. Wei Wuxian relaxed into Xue Yang's firmer grip while she held the first needle in the oil-lamp's flame. She let it cool in the air afterwards, and then she said, "Watch me."

Wen Qing stroked the first two fingers of her left hand down Wei Wuxian's torso, from his collarbone, over the chest and abdominal muscles, lifting her fingers before she reached the waistband of his trousers. It wasn't hesitation: she had known for a while exactly which trail she would lay on his body if she ever found herself here, though she hadn't been anticipating it. Much like her doctor's mind, this part of her never really stopped working.

She pinched up a half-cun of skin over his pectoral muscle. "Breathe in," she said, and he filled his chest and held it, eyes trained obediently on the spot where, with one brisk motion, she thrust the needle into his flesh, through, and out again.

Wei Wuxian let out all his breath in a gargled mess of a sound, jerking upwards against Xue Yang's hands but pinned securely to the bed.

"Fuck, Qing jie," he said, tears streaming from his eyes, "I thought I was ready for that. I was not ready."

"It's good, though?" she checked.

"It's good." He let his head fall back onto the rolled-up cloth that served as a pillow, breathing hard. "It's very good."

"That's going to bruise," Xue Yang said, and she turned a fierce look on him. He wasn't looking at the needle, though, but at the spots where the heels of his hands had dug into Wei Wuxian's pale flesh. They were both too bony for this to be fully comfortable.

"Well, that's up to Wei Wuxian," she smiled. "It won't if he holds still."

Blood was welling up at the two points where her needle had pierced his chest. Without any more fuss, she took the next needle from the roll and held it in the flame until it glowed. Behind her, they were whispering.

"You like this, Wei qianbei?" Perhaps he didn't realise how little that sounded like a taunt, how much like a plea for reassurance.

Wei Wuxian's voice came from low in his throat. "Just keep your hands on me. Don't worry about bruises."

When the second needle went in, on his other pectoral, he hissed and his eyes rolled up into his head. On the third, one cun further down, he groaned, and by the fourth, it was hard to tell how much of his reaction was pain and how much pleasure. She tapped a nail on the outer ends of the needles, one two three four, to enjoy the musical scale it pulled out of him. Xue Yang gasped in sympathy with every one.

"Two more," she decided. She could have spent the rest of the night this way, as long as Wei Wuxian would let her, but she was mindful that his apprentice had a lower attention span than either of them. Right now, though, he looked hypnotised. His eyes were round and black, darting between Wei Wuxian's lips and the blood on his chest.

"Wen daifu," Xue Yang began. He shook his head. "Jiejie? I want—"

"Not jiejie. You can call me Qing jie, like he does." She considered. "Tonight, anyway."

"Qing jie, I want to..." He was considerably taller than her, but somehow contrived to look up at her. One of his sharp canine teeth was resting lightly on his lower lip; it made him look not like a young boy, but like someone who had learnt how advantageous being taken for a boy could be. She had seen him with a knife in his hands, and with a brush, too, daubing additions to Wei Wuxian's diagrams that had, more than once, made him pause and rethink whole theories. She had been prepared for this.

"If you're careful," Wen Qing began, drawing out the second-to-last needle from the roll, but before she could finish he was gulping, "Thank you, Qing jie," and shoving his mouth against Wei Wuxian's, which opened up desperately against it.

They kissed roughly, harshly, teeth and lips colliding. Xue Yang had pushed his hands up into the loose mass of Wei Wuxian's hair, head turned to the side and arms held cautiously so as not to jar any of the needles seated in his skin. Wei Wuxian was whimpering softly into the kiss, eyes shut tight, his hands hovering somewhere in midair as if he wasn't sure if he was allowed to touch. They made an oddly compelling sight. How long had it been since either of them had been kissed like this, she wondered.

For herself, she would have been able to calculate it to the day, but she pushed aside the memories of those stolen Nightless City moments.

She let them carry on until after Wei Wuxian's hands had alit on Xue Yang's waist, until the younger man was rocking his hips against the stone platform and she really did start to worry about stray movements causing an accident. Then she said quietly, "Enough."

Ignoring their guilty expressions, she placed a cool hand at the base of Wei Wuxian's throat to hold him steady before removing the medicinal needles, so smoothly he barely noticed it. His lips were red and his face had more colour in it than she'd seen since they'd arrived here, even the times they'd drunk together. Xue Yang's left hand, the mutilated one, was at his shoulder: not restraining him, just touching, holding.

She felt a startling rush of affection, for the two of them and somehow for herself as well. Her selfish desire to make Wei Wuxian bleed just a little more mixed with the impulse to offer him something just for himself.

"I said two more," she said, "but it doesn't have to be two of these. Do you trust me?"

He had to grope for the words. "Would I be here if I didn't, Qing jie?" he asked after a moment, one hand flexing where he'd left it on Xue Yang's hip.

"Then sit up," she said, gentling her voice. She tugged at the waistband of his trousers. "A-Yang, take these off for him."

"With pleasure." He'd startled at the diminutive, but being given a task—or just an excuse to get his hands on his qianbei—focused him rapidly. Leaning in again to mouth at Wei Wuxian's neck and chest, he slid his fingers under the fabric and eased them down. It took him a moment to realise that he wasn't meeting the resistance he might have expected.

"It's not that I'm insulted," he began, raising one eyebrow at the soft dick nestled vulnerably between the exposed thighs, "but..."

Wen Qing, who had taken the opportunity for a brief inspection of the raised scar that swooped across Wei Wuxian's lower belly, simply took him by the chin and turned him back towards Wei Wuxian, who was pushing himself upright, his face beginning to fall. "Shush. Just take care of him for a moment, all right?" Once he'd recaptured Wei Wuxian's mouth with his own, she added, "Good boy."

This was a tricky thing to get right—not just technically, but because she didn't want her final two needles to get in the way afterwards. She couldn't occupy herself with explanations at the same time as identifying the necessary acupoints. Fortunately, Xue Yang's distraction was an effective one for both the others.

She knew she'd been successful when Wei Wuxian gasped and pulled back from Xue Yang to stare down at his steadily growing erection.

"Wen Qing," he said, a tremble in his voice. "It's been... a while, since that last happened."

"Resentful energy is yin in nature," she said evenly, "and without the usual mechanisms for balancing it out..."

As she spoke, Wei Wuxian reached down to stroke himself, tentatively at first but then more firmly, his mouth dropping open. Xue Yang watched with narrowed eyes, clearly trying to decide just how much of a fuss he wanted to kick up demanding explanations, or whether it was better to keep pursuing the evening's pleasure instead.

Wen Qing, meanwhile, untied the sash around her waist, walking around the stone bed to crowd into Xue Yang's space. The candles were burning lower, she noticed; one or two had already extinguished themselves. As an afterthought, she blew out her sesame-oil lamp. It wouldn't be needed any more for now.

"I can't do this for you often, but I thought you might like it for tonight," she said apologetically, and unpicked the knot of her last inner layer. Her robes fell open about her, revealing a long strip of pale skin.

Just then, Xue Yang made up his mind and stretched out his hand to join Wei Wuxian's. She grabbed him neatly by the wrist and tugged on it, spinning him around to face her.

"You can touch him, A-Yang, but not yet." Wen Qing smiled sweetly at him. She slipped her robes off her shoulders. "Keep hold of his hands, please, A-Xian. A-Yang, use your mouth only."

"I've still got my teeth," he grinned. It was a token protest: his head was already dropping towards her breasts.

"Would you like to keep them?"

Xue Yang only hummed, taking her right nipple between his lips with improbable gentleness and sucking. He had to pull forwards to do so, against the hold Wei Wuxian had on his wrists—and that jostled the needles still embedded in the skin of his chest. At his surprised hiss of pain, Wen Qing felt herself grow deliciously wetter, warm and pulsing.

She let Xue Yang divide his attention between her breasts for as long as she could stand it. He, it seemed, would be willing to spend the rest of the evening there, kissing and licking and even biting a little. I'm growing sentimental, she thought, when the challenging look he shot her through his eyelashes, the first time he grazed her nipple with his teeth, made her smile at him instead of snapping a reprimand. She touched herself as he worked, little strokes just to take the edge off.

Eventually, though, she couldn't take any more. Pushing down her trousers, she stepped away from him and hopped up onto the bed. "Make space for me?" she asked Wei Wuxian, who spread his legs so she could settle in between them and lean against his stomach. She didn't even have to ask him to touch her breasts; he curled over her almost protectively and took them in his hands, brushing his thumbs over her nipples until she squeaked in a very undignified way.

Xue Yang hesitated in front of her, watching them as if hypnotised, like a mouse in front of a rearing snake. Wen Qing braced her feet at the end of the bed, making it as clear as she could where he was wanted.

"You can keep using your mouth," she told him, and he pushed forwards like a swimmer, suddenly looking uncertain and younger than his age, meeting the cleft of her with his lips, his nose, and a tongue that couldn't decide whether to be fierce or delicate. No teeth, at least. For a moment, she wondered if her own sheer arousal would be enough to carry her through an uncertain performance. He had been good at taking direction so far, though, hadn't he? Strung between Wei Wuxian's hands and and Xue Yang's mouth, to say nothing of the hard cock digging into the back of her neck, she pulled out the words she needed to control him—up, harder, yes, now down—lighter, deeper—your fingers, your lips, yes, like that—and he followed everything she said until she was no longer coherent, no words left, only sighs and shaking screams.

When she'd taken everything she could from the two of them, she let herself collapse into the sheets over the straw and just listen to them enjoying one another. She had the vague idea she was supposed to be in charge, that it was her responsibility to keep things moving, but Wei Wuxian and Xue Yang seemed to be handling things fine without her. Wei Wuxian didn't even kick her off the bed when he freed his left leg from underneath her.

He did knock her oil lamp onto the ground to shatter irreparably, but she decided she didn't care about that.

Wen Qing surfaced in time to see Wei Wuxian leaning up against the stone platform, come-splattered and gasping and shuddering in the light of the last candle still burning, as a naked Xue Yang sucked desperately on his cock. Meeting his dark, pleading eyes with her own, she leaned her head tenderly on his shoulder and held him tightly as he came.

They pulled the bedclothes down onto themselves and slept on the floor, while the night melted away and left only the fog of resentful energy to cover up the Burial Mounds around them.