Mercy

SUMMARY

“I’ll do anything.” Childe says it in a low voice, so hushed that Lumine almost doesn’t catch it, but she does, and the words ignite a fire in her.

“Whatever you ask of me, I’ll do it,” he adds.

Direct sequel to Honey Trap.

NOTES

This is for Lumichi Week 2022:

Day 4 - Devotion; Day 5 - Bondage

See the end of the work for more notes.

“I will need more than a marriage oath for you to prove your loyalty to me,” says Lumine, pulling on the collar of Childe’s coat. She sees him subtly tugging at the restraints tying his hands behind his back, but to no avail. Lumine had seen to it that it was tight enough, but not too tight that it cuts off blood flow.

“Marriage contracts, after all, don’t stop people from being terribly unfaithful to their spouse,” Lumine coos, tracing a finger under his jaw. “How can I trust you would be loyal to me, and only me? How do I know you won’t betray me? Won’t stab me in the back?”

Lumine takes his chin and tugs upward to face her. Childe is a mess of sweat and tears, and she just wants to mess him up even more.

“L–let me prove myself to you,” he says. He steels himself as he talks, his brows furrowing to show just how serious he was.

“And just how do you propose such a thing?”

Childe swallows. “I’ll do anything.” He says it in a low voice, so hushed that Lumine almost doesn’t catch it, but she does, and the words ignite a fire in her.

“Whatever you ask of me, I’ll do it,” he adds.

She studies him. It’s one of those moments when Childe would look at her with so much adoration dripping from his dull blue eyes. Even after all these years of being married to him, Lumine still doesn’t know whether to be delighted or disgusted by it. It’s not that she doesn’t love him, because she does, she truly does, in whatever kind of perverted ‘love’ that means lying and manipulating her husband every single day for years and betraying him right in the end when he was no longer useful. And she knows, Childe loves her too, in his own twisted way that means he would follow her to the ends of the earth, no matter what.

Lumine has lied and lied and now, the truth has been so distorted that she doesn’t know whether to believe Childe or not. Not exactly the healthiest relationship, but when has this ever been healthy? So, she decides.

“If you would be loyal to me, then you will do as I say,” Lumine replies, her voice soft yet stern. “You will obey me without question.”

“I’ll do it,” he answers.

“Did I say you could speak?”

There’s a conflicted, terrified look in his eyes. He must be searching for the woman he married. She was never there, Lumine wants to say. You married an idea. Not a person.

“This is not an equal partnership, Ajax,” Lumine says, ice in her voice. Childe visibly shudders when he hears his name—a name only his blood family calls him. And sometimes, she calls him that when she is furious with him, uttered more like a curse than the affectionate way his little siblings do.

Lumine grasps his hair and pulls him back, loosens the red scarf and exposes his pretty little neck for her. She leans in and grazes her teeth on his skin, a low growl rumbling in his throat. Lumine sinks her teeth in and Childe gasps at the contact. She sucks and bites and licks, and god, Lumine can already feel him squirming under her, wanting. She emerges from his throat, her fingers still entwined in his copper strands. A bruise blooms on the spot. A reminder that he is, and always will be, hers.

Not the other way around.

“This was never an equal partnership. I was always one step ahead of you, honey, even now,” she coos, tracing the outline of the bruise, poking it softly.

Childe does not say anything. He only stares. There’s adoration in his eyes again, and Lumine decides it is disgusting. Even after all this time, after all the lies and deceit, and the suffering that lay ahead of him, he still looks at her this way? Lumine wants to punish him, hurt him in every way she knows. See if he knows what’s good for him. If he will still beg to be with her after.

He’s still staring, this time with that very subtle expression of his. The one he uses whenever they have a fight and he wants to apologize. To be absolved. She steels herself. She will be strong. Will not be swayed by his stupid puppy eyes.

Lumine fully unravels the red scarf on his neck and wraps it around his eyes like a blindfold.

“No tugging at your restraints. Absolutely no necessary movement. Do you understand me?”

He nods.

“Good.”

Lumine steps off him and kneels down in front of Childe. “Any movement at all, and I stop. Understand?”

Another nod.

She spreads his knees apart and caresses his thighs. Her fingers trail along his inner thigh, inching languidly towards the center. Beneath the fabric of his pants, Lumine sees a brief movement. His cock, twitching from the touch. She palms it, caressing its length. It stiffens with the massage, extending under her fingers.

Lumine looks up at him, teeth biting lips in an effort to stifle a groan. Smiling, she undoes his belt and zipper. She licks her lips in anticipation, pulling down his trousers just enough to pull his cock out. There’s precum already leaking and good god, Lumine wants nothing but to sit on him and ride him until he’s about ready to pass out from dehydration.

But she will be patient. She will practice self-restraint. This is for his own good.

Lumine takes hold and swipes her tongue across the head, cleaning off the precum. Childe breathes loud through his nose, chest heaving deep, controlled breaths. She licks him again on the underside. He twitches, such a minuscule action, but Lumine knows full well how much she is already driving him crazy.

She takes him in her mouth, slowly but surely, from the head, down fully to the base. The hair tickles her nose. Lumine stays still, breathing through her nose, and then she swallows. His favorite. Her throat closes in on his head and it takes every thread and sinew of his muscles not to twitch and moan. Lumine hums with satisfaction, and again, she knows the vibrations of her vocal cords feel so, so good on his cock. She pushes onward, his cock encroaching her throat. On reflex, Childe’s hips buck forward, fucking her mouth for half a second before Lumine pulls away. His cock slips out of her mouth with a pop. Childe lets out a soft whimper.

Lumine stands up and sits on his lap, straddling him, making sure his cock isn’t touching her. Her fingers wrap around his throat, and she squeezes.

“What did I say about moving? Hmm? Speak.”

“You’ll stop,” he wheezes.

Lumine squeezes tighter, admiring the way her fingers fit around his throat. His neck is too wide for her, but her hand span is wide enough to press on the pressure points, to simulate that feeling of being choked.

“How am I supposed to trust you if you can’t even follow one simple instruction?”

“I’m sorry,” he pleads. “I’ll do better. Please.”

“Are you gonna be a good boy this time, hmm? Are you gonna behave?”

He nods. “Yes, I will. Please.”

Lumine lets go. “If you disobey me again, I will not be so merciful next time.”

He nods again, desperate.

“Good,” she mutters, leaning forward to kiss him. He moans into her mouth, earning him a bite on his lips from Lumine. “Quiet.”

“Are you ready for this?” Lumine whispers in the shell of his ear. She hikes her skirt up, grinding down on his cock, so hard and wet, so ready for her to take. “Seems like you already are, honey.”

Childe bites down at the sensation. He nods again.

“Maybe you deserve a reward after all,” she says, tracing his jaw. “For being so ready and eager for me.”

Lumine pulls her panties to one side and slides the tip of his cock into her wet pussy.

“You’re mine, Ajax.” In one swift motion, she takes him in fully inside, and they both sigh, almost in unison. “You’re all mine. All of you. Every inch—” she says, slowly riding him. “—belongs to me.”

Childe nods, humming affirmations.

It feels good, so good, to have him inside her, like he was made for this, his cock molded to fit her pussy so perfectly. It is even better like this, with Lumine riding him, like he is her personal toy. A human dildo to be used by her, to fill her up whenever she wants.

But it is not enough. His loyalty needs to be tested and questioned, and in his state, it is too easy for him to please her, to say appeasing words. Lumine takes off the blindfold, and he smiles the instant he sees her, like a dog wagging its tail in excitement. She smiles back, too, but only because of what she says next.

“You’re mine,” she begins, and he nods at her words as she continues, “but you’re not good enough for me.”

The smile on his face fades. Good.

“I’m too good for you, even before all this,” Lumine says, panting as she rides him with reckless abandon, “and you know it, too.”

Childe tries to lean in, maybe to kiss her, to silence her, but Lumine holds his face in place, caressing his cheek affectionately. Her hips are relentless, snapping up and down on his cock, filling the room with obscene slapping noises.

“You know I’m too good for you, that I deserve better than you—” Lumine leans forward to kiss him, “—but that’s why you love me, isn’t that right? That’s why you want me. Because I’m better than you in every way.”

Lumine slows down. She studies his face, his reaction. He’s silent as she has commanded, but his brows are furrowed. She can’t tell if he’s indignant at her words or if he’s processing them, accepting it as truth. Will he accept it as truth?

The more important question is, did it hurt him enough?

Lumine decides to deliver the coup de grâce. She needs him to hurt. “Even though I don’t love you, even though you’re nothing but a toy to me, you love me anyway.”

And it works.

“Fuck you,” Childe mutters.

“What did you say?”

“I said: Fuck. You.”

Lumine chuckles. “It’s true, isn’t it?” She starts riding him again, pushing down on his shoulders.

Childe throws his head back, his eyes screwed shut, biting his lips. “Fuck, Lumine.”

She ignores his disobedience. It might be better this way; Lumine gets to hear him be angry and aroused at the same time. He can talk all he wants, but in the end, all he can do is take it, take everything that Lumine dishes out to him, whether it be hurtful words or her perfect pussy. So absolutely helpless.

Lumine ramps up the pace, the kind of pace that gets him close to the edge. And it shows, with the way Childe is panting shallow breaths, muttering curses in every language he knows, like a litany or a prayer, and then, “Lumine—”

She stops.

“Fuck!” he yells.

“Did you really think I’ll let you cum before I do?” When he doesn’t answer, she continues, “Oh, so now you’re silent? You have been misbehaving, speaking out of turn, Ajax.”

She can’t decide whether she wants to him quiet or not, really. But it is fun, so fun, playing with him like this.

Lumine doesn’t break eye contact as she brings her fingers down to her clit. The sensation makes her pussy clench around his cock, making him twitch inside her. Fuck, it feels good.

“You don’t cum until I say you can,” she says. “That is how this works.”

He nods.

“But you’re close, aren’t you?” Her fingers pick up the pace. “I know how badly you want to cum right now. I know all the ways to get you there, and I know this—watching me touch myself—gets you off so good.”

She keeps talking. “And it gets me off so good, too, honey. Knowing that you can’t do anything else but watch, can’t even make yourself cum just to end it. It gets me off that your pleasure is in my hands, and here you are, being an obedient little boy for me.”

Ah, she’s close. The anguished look on his face is perfect, is just what she needed and—

Lumine holds on to his arm as she climaxes, riding her fingers and his cock, her pussy clenching along his length, and oh, why did she wait to do this when she could have had this all this time?

She brings her slick fingers to his mouth, and as if on instinct, Childe licks and sucks her clean, so well done that Lumine has to wonder if he has ever sucked cock before. He would definitely look good with a dick in his mouth.

Lumine rides him lazily. Childe groans, and he sounds so good like this, so undoubtedly tortured and desperate for release. It makes her just want to hurt him more and more. She wants to know what his breaking point is, what will make him snap. If he even will snap. Will he ever realize how terrible she is and walk away? Or will he feign ignorance and come back, despite it all?

Breaking him beyond repair shall be saved for another time. For now, Lumine only wants one thing.

“I’ll let you cum,” she whispers, “but first, I need you to swear to me. Promise me.”

A promise—such a sacred thing in Snezhnayan culture. Spiritually binding contracts. A blessing to those who keep them, a curse to those who break them. The wrath of gods comes down to anyone who dares break a promise.

Lumine does not believe in gods, but she knows Childe does.

“Promise me, honey, that you’ll obey me,” she coos in his ear, “That you will do anything I ask. No matter what it is.”

Childe is silent. He knows the gravity of making this promise. On their wedding day, he had used the same word, vowing to love her till the end of time, but that is not enough. Lumine needs more than love. She needs absolute, unquestioning loyalty.

Lumine picks up the pace again. “Promise me to stay by my side. To answer to me always.”

He groans, and there’s a film of tears in his eyes, threatening to spill.

“Promise me, and I’ll let you cum.”

Finally, Childe nods. “I promise.”

“Say it.”

“I–I promise,” he starts, stammering, “to stay by your side and—and do whatever you want me to do. Please, Lumine, I can’t—”

Lumine leans in, kissing his forehead. “Good boy. You may cum.”

She keeps a fast, steady pace, and Childe lets go, groaning. “Ah, Lumine—”

She goes on, feeling his cock twitch as he comes and spills inside her.

“So good, so obedient,” Lumine says, sweeping the matted hair off his forehead, wiping the sweat away. She touches their foreheads together and they remain still. In their proximity, Lumine can feel her heartbeat concurrent with his, loud and fast, gradually slowing down.

It is done. Lumine has what she wanted from him, and yet, she does not understand. Paranoia creeps from within, planting seeds of doubt in her mind.

Before she can stop herself, she mutters, “Why?”

“What?”

“Why?” she repeats. “Why did you want to join me? Why did you want to prove to me—why did you say you’ll do anything—”

Childe leans back and looks at her. “Because I love you,” he says, like it’s supposed to mean something to her.

Does it?

Words mean nothing to her. They are just a way for her to get what she wants. Lumine can make them mean anything, weave them into whatever little lies anyone wants to hear. But now that she has it—that Childe has said it, has promised his life to her—Lumine can’t find herself to believe him. To accept, to trust that what he’s saying is real and true. Because, after all, words mean nothing to a liar like her. And maybe this is the price she will pay. Her own little hell she built for herself from her lies and secrets.

But does the spider feel sorry for the insect she has lured to her trap, for devouring him after he so willingly landed on her web?

“Y–you should stay in the Fatui,” Lumine says, “Remain as a secret agent for the Tsaritsa.”

“What? What are you saying?”

“It’s not what you think. I... I need you to be my insider. Keep up the image that we had—you as an agent hunting down the Abyss Order and me as your clueless, loving housewife.”

Childe scowls. “I thought—I thought I would be working alongside you. With you. In the order. Not... whatever this is.”

“You will.”

“If Her Majesty finds out, it will be my head—”

Lumine shushes him, bringing a finger to his lips. “I am your majesty, Ajax. Remember your promise. Or do you not love me at all?”

“I do. I do.”

“So, you’ll do it?” she asks, as if she is giving him a choice in the matter.

Childe swallows and nods. “I will. For you.”

“Good.” Lumine kisses him, soft and tender.

“Do you?” he whispers, hot breath on her lips.

“Do I what?”

“Do you love me?”

Lumine laughs. “What kind of question is that?” She traces along his collarbone, finger settling on the bruise she had left and pokes it, hard, making him wince. “Of course, yeah. What I said earlier, it’s just dirty talk. Being terrible for fun. You know.”

Childe nods, but there’s uncertainty in his face. The slight twitch of his eye. “Yeah, I get it. It was—it was hot, but...”

“But?” she repeats, drawing out the word.

He looks away. “No, never mind.”

She takes him by the chin to face her. “Hey, come on. What is it?”

“It’s just... It was a little too...” His voice trails off. “It’s just dirty talk, right?”

“Mm-hmm. That is what I said.”

Childe purses his lips. “And you do love me.”

“Honey...”

“Say it. Please.”

Lumine gives him a lopsided smile. It is amusing, really, how he is demanding things of her, like he didn’t just promise he’ll do anything she asks. But she smiles anyway, to appease. To make him feel safe, somehow. Unlikely to betray her if he feels he has power in this relationship.

“Yeah. Sure.” She kisses him. “I may not love you, but I do love you. You know?”

Childe’s lips spread to a thin line. “...I know. I do know.”

Lumine smiles. “Good.”

NOTES

tomshiv vibes, anybody? (i fucking love failmarriage dynamics so much)

Also this is my first time writing something that is... not vanilla? Even though this might be considered only mildly un-vanilla, but hey, whatever. I had fun writing this 👌🏼

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