The Third

A.N.: realized I forgot something important for Ariin when she's going over her Boons - for those who have already read the chapter, the literal only difference is that Ariin also has Parental Mastery as a boon - it's all of one short sentence, so probably not worth re-reading.

Ahsch stared at his sister, his stunned, open-mouthed expression nearly comical. "You... but that... how...?"

"Always," Ariin interrupted his stammering, though she looked down, not able to hold his gaze for very long. "I've... I've known since always. Growing up, I just... I knew that you were once a man from another world. That you were reborn here of your own choice. I've known about Dominant's Tithe, your many Boons, your potential to grow beyond almost anyone else... I... I think that they... I think one of those 'office people' tweaked who and what I am." She looked back up, meeting her brother's eyes. "For you."

He was only able to stare, mouth dry. There was a tense silence for a moment, then Ariin let out an almost broken laugh. "I think, hearing this, you probably understand why I... resented you when we were younger. You were the special one. You got the choices. And I was... I was jealous."

Ahsch knew exactly what his twin was talking about. When they were young children, all the way up until she started using magic, Ariin seemed hell-bent on getting in his way. She interrupted him when he was studying or practicing, hid his books, and just generally made a nuisance of herself. He'd always believed it was just... childishness. But now certain things started to click into place. Looks she gave him when he misspoke, different, more... knowing that the ones the rest of the family gave him. Her expression when he told his family that he generated mana with Mahat. The jealousy when he was the one to dreamweave first.

"What changed?" he finally managed to ask.

She gave him a small smile, then turned to look at Mahat. "She told me to get my head out of my ass and figure out my life."

That got Ahsch to glare at his familiar again. "You transformed when she was a kid? I thought you said there wasn't ever a need?"

The fox-girl gave him a pacifying, placid smile. "No need for you to see my humanoid form, Master. But I don't have a mental link with your sister, so I needed to be able to talk to her."

"And it was a good thing she did," Ariin continued. "She got me to see that, even if I was altered, tailored to be your sister, that didn't mean I had to build my life around it. I wasn't bound to you, I didn't have anything aside from our blood and our mother's womb that tied me to you. They could make me into your perfect companion, but I could choose to be your enemy... or your perfect sister. And I did.

"Mahat told me you could recall the 'System Description' of all of your choices from that... in-between place. And I found I could do something similar. I had at least a basic knowledge of your choices, but I could picture my own Mana Generation Method, Boons, and Innate Spells in practically the same way, with perfect clarity. And, comparing and contrasting the choices... well, it's clear that I was, in fact, tailored to be yours."

"What do you mean?" Ahsch had a sinking feeling he knew exactly what she meant.

"I don't know how well you remember all the choices you didn't take, but here's the list: I'm an Exhibitive Mage, meaning Exhibitive Creation is how I generate my mana - the same as what you had as an option, where it's like Ambient Absorption, but scales with how much skin is revealed. That's why it's so 'weird,' as I once told you. I also have three Boons, none of which you took: Protected Power, the opposite of your Pierce Boon - it helps to keep my magic from being canceled out; Sexual Amplification, which you couldn't really take with Ecstatic Generation, but functions as a power-up based on having sex; and Mystic Domain, which lets me infuse the land with my magic, creating a Ley Spring and generating ambient mana. I... also got one of the Boons you did take - Parental Mastery.

"I also have an Innate Spell that's about as weird as anything you were offered, but you didn't get it as a choice..." Ariin blushed, glancing away again. "Arsenal of Ecstasy. It... it strengthens me, makes me faster, more durable, increases my coordination, and even gives me a boost to my mana generation; but it has a few of those 'weird' bits. It scales like Exhibitive Creation does - the less I'm wearing, the stronger it is, and it scales with how aroused I am; it also makes me horny, increasingly so over time; and it cancels if I orgasm."

Ahsch's eyebrows felt like they were hiding in his hairline. He remembered the basics of the four options he declined on, but Arsenal of Ecstasy just sounded like a joke. A very powerful joke.

One that was too-perfectly matched with his Dominant's Tithe's new capability of preventing orgasms.

"I'm guessing that Mahat might have already told you about the 'gift' that Phashak gave me? The bits that we didn't report?"

Ariin smiled. "Yes, she did. Our siblings make for great distractions."

The boy chuckled. "I think I understand why she was making the suggestion she made earlier."

His twin frowned. "There's more to it than just that, brother." At Ahsch's tilted head, she continued, "As I was saying, Mahat got me thinking about what choice I'd make for the direction of my life. And the more I thought about it, the more I realized that my resentment of you was... well, it was stupid. It wasn't your fault that I was made into this, or that you were given the opportunity you were. It would be dumb of me to blame you for taking the best choices available to you. And I couldn't say with any certainty that you taking the 'good' options kept me locked out of those same choices - we both have Mage Sight, after all. And festering in my hatred for what those... I don't know, gods? did to me was just as pointless, given that I can't do anything about it.

"So since I didn't want to hold on to that hate, I basically had two choices. I could just accept that things are the way they are, and move on with my life in my own way. You'd be my brother, and I'd be your sister, but I'd make my own path. Or... I could follow the path that my... my gifts offered, and become yours. She might have been biased, but Mahat made good arguments for the latter, and... that's what I chose." Ariin slowly sat up, one hand caressing Ahsch's chest, the other his thigh. "With her help, I memorized your System Descriptions. I learned what you needed that your familiar couldn't provide. And... and I made myself into the best helper... the best servant... the best _thrall _I could." Her hand drifted from his thigh to his slowly-hardening cock. "And I decided that, when I gave myself to you - mind, body, and soul - that I would also become your first worshiper."

Ahsch's mouth was bone dry again. He could hear his heartbeat in his ears, feel it in his neck and temples. But he couldn't speak. On the one hand, the part of him that only a few hours ago had been rejecting the power he could have over others was screaming, panicked that his sister, someone he cared so deeply for, was going to surrender herself to him like that. Because it was wrong.

But so much more of him felt... complete. There was a new sensation within his soul, and he knew it was Object of Worship gaining its first worshiper, just as Ariin had said.

"There's nothing specific for a Thrall's Oath... Master," Ahsch shivered as the words left his twin's lips, though it could also be from her shifting up, straddling him, her hot, soaked cunt grinding against the underside of his cock. "It belongs to each Thrall individually, their own gesture of submission. So... I, Ariin, daughter of Dahil and Noeh, swear my loyalty and submission to you, Ahsch, son of Noeh and Dahil. I will obey you, love you, and worship you, until the day I die. I offer my mind, which I dedicate to serving you. I offer my body, your tool to use as a weapon, shield, or toy. I offer my soul, yours to own and posses. You will be my Lord, my Master, my... God, forevermore."

As the final syllable left her mouth, the Dominant Mage felt the third bond lock into place, at the same time that Ariin shifted forward, lodged the tip of his cock at the entrance of her pussy, and then slammed back and down, sheathing her new Master's cock all the way inside her in a single, quick act. The siblings let out twin moans of ecstasy, Ahsch's deep and growling, Ariin's a keening whine.

After taking a moment to revel in the sensation, the girl began to rock her hips, her belly undulating as she all but danced on her brother's, her twin's, her Master's cock. Her one hand was still on his chest, keeping her balanced, while her other hand caressed her own body, stroking up and down her thigh, hip, and waist, cupping and kneading her breast, pinching and twisting her nipple, playing across her lips, and fanning out her hair. She stared down at Ahsch with almost obsessed intensity, lust and... yes, he saw the worship in her eyes.

He came as that realization sunk in, her Oath and the sheer debauchery of her submission riling him up more than ever before. But Ariin didn't stop, and he didn't soften after dumping his first load in her tight, pulsing cunt.

"Isn't she just delightful?" Mahat whispered into Ahsch's ear. "Your own sister, your twin, wrapped around your dick like an... what was it called? An 'onahole?'" The hrafthi boy groaned, prompting an almost purred laugh from his familiar as she took a quick lick of his ear. "Every time you cum in her, it's like you're claiming her as yours all over again. Marking your territory. Making her your Thrall... your ****. Maybe, someday, you'll make that mark obvious for everyone else... when you knock her up with your baby."

Ariin must have been able to hear Mahat, because at those words she slammed her hips against her brothers and her cunt went wild, convulsing and squeezing as though in orgasm - but Ahsch knew she wasn't.

He hadn't let her cum, after all.

"Just think about it, Master. Breeding her tiny little body, making her belly round with your child, her tits heavy with milk. And you don't even have to worry about the consequences of inbreeding."

"Fuck," he grunted, the image going through his mind.

"That's not even the start, Master," Mahat continued, her breath hot against his ear. "She's your first worshiper. The first to have faith in a new god. And what's a god without a religion, a cult?" Ahsch felt his breath catch. "Yes," the familiar hissed. "Your sister, your ****, your priestess, preaching to the masses, extolling your greatness, and tempting more delectable little things into your bed and service. You could be a god of debauchery, of lust and pleasure, of dominance and submission. A master to a whole religion of slaves."

The Dominant Mage was breathing heavily, his mind spinning with the images Mahat was suggesting. It's possible, isn't it? he realized. With my nigh-infinite growth, the number of Thralls I could take is limitless...

He could see it: himself upon a fine throne, at the end of a monumental hall. Ariin stood ahead of him, proclaiming his greatness while her body swelled with his child. Mahat was curled against one of his legs, gazing adoringly up at him. As were a dozen others, their bodies adorned with little more than sheer gauze and titillating jewelry, and a couple of them tended to his cock with worshipful mouths. One Thrall stood by with a platter of ripe fruits and nuts, another taking individual morsels and feeding them to him. Out beyond the dais of his throne, a throng of women were bowed in supplication, worshiping, pining for his attention...

"You could have it, Master," the real Mahat moaned into his ear. "You could have all of that and more!"

He could. It was entirely within his reach.

And yet...

Ahsch reached up, firmly holding his sister by her hips, stilling her grinding. "I could. But... I don't have any delusions of grandeur."

"Master!" both girls started to complain in tandem, but a sharp look from him brought their words to a halt.

"That's not to say that I'm entirely opposed to all the ideas you've suggested. I just... I don't want to become some... thing that sees itself above others. If I am capable of becoming a god, I owe it to myself and everyone I could help to use that power for the betterment of people, not just my own hedonistic whims." He cracked a smirk. "But that doesn't mean I can't... indulge myself."

Taking an active role for the first time in the encounter, Ahsch sat up, then laid his twin out before him as he got up on his knees. He took several long moments to explore her body with his hands, enjoying the way she writhed and squirmed at his touch. Once he'd satisfied his desire to feel her, he lifted one of her legs up and against his shoulder, then began to languidly thrust, drawing long, passionate moans from his sister. Reaching out, he sank his fingers into Mahat's mane of silver hair, using his grip as a handle to drag her close.

Holding his familiar nose-to-nose, he smirked at her. "I really ought to punish you for keeping such a delectable body from me."

She smirked back. "Remember, you can't lie to me, Master," she teased.

He laughed, then pulled her into a crushing kiss, still thrusting into Ariin, who ground back at him. After a minute, he broke the kiss, directing Mahat with mental commands to lay on her back just beyond his twin. As she did that, he flipped his new Thrall onto her belly, pulling her hips up so that her ass was up, and pushed her head down in between his familiar's spread legs. Mahat's moan of pleasure told him that his sister had put her tongue to work right away.

He picked up the pace, his hips slapping against Arrin's tight ass with each thrust, while Mahat moaned and bucked her hips into the hrafthi girl's skilled mouth. He watched, keeping his new pace, until the familiar had cum, then ramped up again, slamming into his sister with abandon, raining smacks down on her ass with one hand as he reached up to grab a fistfull of her hair and yank her towards him, her back arching sharply as she cried out in erotic joy.

Ahsch saw movement beyond his twin, then felt a tongue at the junction of their bodies, as Mahat started to return the oral favor. Growling, the boy pulled his sister in close, embracing her from behind, on hand wrapping tight around her throat while the other roughly groped her chest. "Do you want to cum with me?" he snarled into her ear.

"Whatever you wa-ahnt, Master," she gasped, her panting moans so deliciously lewd.

"And if I want to keep you on this edge for days? Weeks? Months?"

"You own me, Master!" she exclaimed. "If you never want me to cum again, that is your right!"

Ahsch nearly came from that proclamation. Indeed, he controlled his twin's orgasms completely. Unless he allowed it, she would never cum again.

"Tonight," he gritted, on the verge of cumming himself, especially once Mahat began to gently suck and kiss his balls, "I will reward your submission. You can... no, you _will _cum with me, Ariin." He groaned. "Ariin. Sister. My twin. My Thrall. My. Little. Bird!" He slammed in, feeling as though he was breaching her womb, and as he came he felt his sister's cunt convulse around his cock, her voice screaming out so loud that she went silent as she shook like a leaf in a storm.

Ahsch was so overwhelmed with pleasure that his hips jerked back and forth several more times, making him feel like he was going ever deeper in his Thrall as he shot load after load into her. Ariin suddenly went limp as the last pulse of his cock ended, and he barely kept himself upright as she collapsed. Mahat managed to catch the hrafthi girl, gently lowering her to shiver and moan softly on the bed, then tended to her Master, gently pushing him to lay back before leaning down and taking his cock into her mouth, oh-so-gently cleaning up Ahsch and Ariin's mixed juices before settling in to gently suckle.

As he started to drift off to sleep, the boy felt his sister weakly crawl up beside him. She once again found her spot, nestled under his arm, his hand resting on the cheek of her butt. She rubbed her face into his chest, and breathed out, "Thank you, Master."