Anal play isn't one of my kinks, but power exchange is, which is why I decided to do this prompt fill. That and boredom and a desire to try something new. So this might not be the best, but I figured I'd give it a shot. Please, please, please comment and let me know what you think. Feedback is my drug of choice, and the more I get, the more motivated I am to write more.

But be warned there is a fair amount of graphic maturity that follows.

There were some things that Commander Ralleigh Shepard's Alliance training and purely and quite simply neglected. There were a wide range of topics covered in her Xenospecies Cultural Sensitivity course: everything from Asari music to Krogan biology to the very odd Salarian reproductive habits. The course was filled with practical information, but the topic was just too broad to adequately elaborate on all the nuances of each species.

There was a lot Shepard did not know, and she would be the first to admit so. There were many things she had picked in her career through time and experience. It was considered impolite to call an Asari a "smurf," and besides the reference was lost on them anyway. Krogans appreciated brash, dominant behavior and aggressive posturing, which was not so different from pubescent human males. The Quarians were regarded by the rest of the galaxy in a way similar to the Mexican immigrants of the twenty-first century, and Turians clicked their mandibles whenever something amused or annoyed them.

Even after years (of which two Ralleigh had been technically deceased) of being intimate with Liara, of being her lover and partner and bondmate, she still found gaps in her education. References that soared gloriously over her head, words that did not quite translate, subtleties that confused her. Liara was always patient in these instances, carefully explaining whatever it was that Shepard had missed. Ralleigh suspected that some small part of the archaeologist turned Shadow Broker enjoyed being able to share her love of knowledge with her.

But it was frustrating to Shepard. Sure, there were probably an equal number of concepts and expressions that bewildered Liara as well, and she did not mind explaining them. But it was part of who Shepard was; she hated that there were things that she did not know. She hated it even more that there were things that she didn't even know that she didn't know. Besides, ever since Ilos, ever since their first real joining, Shepard had given her heart to the young, shy Asari maiden. It wasn't a promise so much as spoken as felt through their mutual bond.

Shepard loved Liara.

And after everything they had experienced together, and everything still to come, she wanted to be the best for her bondmate. Liara deserved that. And Shepard wanted to learn how to better care for her, to understand everything there was about the Asari, their culture, their biology, their history, everything. It was a part of Liara that she wanted to be able to share and understand.

There were things, though, that Shepard had not anticipated. Her furtive study sessions on the extranet were full of Asari composers and turns-of-phrases, cuisine and biotic studies. When she had searched "pureblood," it had been purely to better understand the Asari and galactic perceptions of Liara, of those born of two Asari parents. What she had stumbled onto was something that she was not surprised was never covered in any Alliance sensitivity training.

What was more confusing than surprising was the mere fact that Liara had never shared this information with her. Sure it was extremely personal, but they were bondmates. Liara shared everything with her. All of her insecurities and quirks, her ambitions and idealistic dreams, and Shepard reciprocated. It would have been something that the Asari doctor would have had to deliberately hidden from her during their melds, and Shepard could not understand why.

It was as if centuries of centuries of genetic evolution had conspired solely for her benefit, and if ever there was a moment that Shepard believed in god or some supreme higher power, it was now. As she powered down her private terminal, she smiled and shrugged on her hoodie. No, it would definitely be the Goddess, if such a thing existed, she thought as she tugged on the hoodie's zipper.

As the doors whispered open, Liara knew instinctually that it was Shepard without having to glimpse up from her dazzling dance of information terminals. She was the only person that Liara had trusted with the security override protocols to her quarters, besides EDI of course.

Glyph began his well-programmed chorus of greetings and information for the Commander, but Shepard ignored him as she always did, which caused a corner of Liara's lips to quirk in a half-smile. She did not say as much, but Liara knew the VI irritated Shepard in a way that few things did. What had she said once? Ah… "It's like an annoying little brother that won't shut up while you're trying to get a piece of tail." Perplexing human euphemisms aside, Liara understood and usually activated the silence feature whenever her lover visited her quarters.

Her smile broadened as she felt strong, lean arms snake around her waist, the slight puff of breath on her cheek as Shepard rested her chin on her shoulder. "Hello, my love."

"Shepard—" Liara felt the words die upon her lips as she felt her lover's breath on the back of her neck, her mouth hovering tantalizingly close to the skin.

"I missed you."

Liara felt rather than saw Shepard's smile as lips were pressed against her neck. Removing a hand from the keyboard, she abandoned all her information streams and reached up to rake her fingers through Shepard's hair. It was something that always fascinated her about humans. Asari had absolutely no body hair to speak of, but humans possessed such a wide array of hair in different colors and styles and textures. Shepard's was caught somewhere between red and brown and kept relatively short at chin length.

She loved the feel of it as it slipped through her fingers like liquid silk, infinitely soft. She felt a hint of warmth on her cheeks as she remembered her first discovery, years ago, that hair was not only to be found on a human's head.

"And I have missed you." Liara murmured and leaned back into the comfortable embrace. "Does nothing on the Normandy need the Commander's attention?"

"It's late." Shepard mumbled into her neck, grazing her lips from the collar of her jumpsuit to her ear, causing Liara's breath to quicken. "You should be in bed. With me."

Liara glimpsed at the shipboard clock. "Asari physiology differs from humans as we are not required to sleep at regulated intervals—" She was silenced by a sharp nip below her ear. "I lost track of time."

Shepard gently turned her lover in her arms so that they faced one another. "It's okay. I know how you get. I tried waiting for you, but figured you were eyeball deep in your feeds. So I came to you."

Ducking her head somewhat shyly, Liara smiled as she felt a delicate kiss planted on her brow. "You shouldn't wait up for me. You hardly get enough sleep as it is."

"Who said sleeping was what I was waiting for?" Grinning, Shepard tugged her in the direction of the bed, which caused Liara's pulse to quicken. "Speaking of Asari physiology, I found something interesting on the extranet this afternoon."

"Oh?" Liara's thoughts felt muffled, absent as she allowed Shepard to unfasten and unbutton her jacket and push it off her shoulders. As an information broker, she tried not to invade her lover's privacy too much, but it was no surprise that the Commander had been researching Asari culture and customs. But that did not matter at the moment. All that mattered were those slender fingers that were taking far too long to undress her, that hesitated as they brushed the fabric still covering her breasts.

"Something regarding certain sensitivities in Asari borne of pure unions." Shepard never said "pureblood," even though Liara approached the word as a clinical truth. It bothered the human that such a thing could be said to hurt her lover. But then, the implication of what Shepard had said sunk in and Liara felt her face, Goddess, her entire body flush purple.

"I…" She reached up with her own hands to fumble with the zipper of Shepard's hoodie to mask her trepidation. "I don't know what you're talking about." She risked a glance of her lover's face, only to find that sweet, open smile of affection, of adoration, gracing her lips.

"You've always been such a horrible liar, Liara." Shepard pushed the way the top of the constrictive jumpsuit, her calloused hands finally finding purchase on bare, blue skin. "It's okay—"

Images struck her full force, one after the other. Things she had thought about, things that she fantasized about when she was alone, things that caused her overwhelming shame even in the privacy of her own mind, things she could never tell Shepard. Another Asari would look at her with at least mild contempt, let alone a human who were notoriously more conservative in their sexual practices. "No, Shepard, please…" Without realizing it, she pulled away from her, feeling her face positively burn and looking anywhere but at her lover.

"Liara." Shepard's voice shifted from gentle to sharp. Liara knew that tone; it was the tone that did not tolerate refusal, which carried the weight of solemn threat. It was the tone that caused Liara's heart to jump a little in her chest, that forced her to meet the now-serious face of her lover and return to her. Nudged gently by a crooked finger under her chin, Liara met Shepard's somber green eyes. "It's okay."

Their lips met, then tongues. Shepard mentioned no more on the subject, and evidently accepting that it was not a topic Liara wished to discuss. Now or ever. They kissed, and Liara felt herself melt into the possessiveness of the kiss as Shepard claimed her with lips and tongue and teeth. She was shy to admit it, especially during their first meldings, but the dominating, aggressive images she found in Shepard's mind were exciting.

It was primitive, but the act of being claimed physically and mentally was immeasurably arousing. She enjoyed their times of sweet, languid lovemaking as well. But there was something undeniably intoxicating about being taken, of being used for her lover's pleasure. It made her squirm with anticipation.

Clothes were shed in between breathless kisses, and Shepard's mouth kissing and sucking along her collarbone. Only the commander's trousers remained, and as Liara reached for the buckle of her belt, the commander halted her efforts by pressing against her.

Liara gasped as she felt the firm bulge press in between her legs, sending a shock of pleasure that radiated up her spine and down her legs, and she blushed with the knowledge that Shepard had come to her quarters wanting her. She gasped again, another shock of pleasure making it difficult to stand as sharp teeth marked her shoulder. "Please…" She tugged insistently on the offending belt.

Shepard withdrew abruptly, leaving Liara weaving and unsteady on her feet. She watched the Asari's heavy-lidded arousal as she slowly, torturously so, unbuckled her belt. It hissed through the fabric loops as she removed it completely, and then kicked off her trousers and underwear. The only thing she now wore was the phallic shaft of a human male, artificial of course. A technological marvel, it depended on nerve stimulations at the attaching base to conduct sensation along the length of the shaft.

Liara began to reach for it, to wrap her hand around its length, but Shepard grinned wickedly, having a much different idea. Placing a hand on the back of her neck, the human steered her to the bed, forcing her onto her knees. Another encouraging push and Liara fell forward onto her elbows. Her entire body shuddered with anticipation. This was one of their favored positions, and Liara relished the utter helplessness of the situation. She wanted more, but knew that Shepard would decide when and what to give her.

The bed caved as the human knelt behind her and shifted. Strong hands gripped the front of her thighs from behind, and the ghost of a breath across her backside. Liara stiffened and tensed to push herself up as she immediately understood her lover's goal, but her grip tightened. "Do. Not. Move."

Knowing better than to disobey, Liara fell back onto her elbows, torn between the want that was quickly bubbling into need in her mind and the urge to protest, to keep her shameful desires secret. A firm swipe of her tongue along the crevice of her ass was almost enough to make her cum immediately, and she cried out.

Encouraged by her response, Shepard only probed deeper with her tongue, teasing. But even the slightest stimulation to her anus caused her to sob out loud, her inner walls clenching around nothing as the orgasm wracked her frame. As the tremor subsided, a part of her mind registered that her breath was coming in ragged pants, that her arousal was dripping down her inner thighs, cooling.

"Please…" She managed, and she wasn't sure if she were pleading for more or for Shepard to stop. Goddess, it felt so unbelievably good. Every swipe of that pink tongue made her so wet, and Liara felt herself involuntarily pushing into Shepard's mouth, unable to stop the roll of her hips. "Please, Shepard… don't."

But her lover did not heed her words, paying attention instead to the pleas of her body, the unspoken need that was indirect contradiction to what Liara was asking her. Fingers dug into her thighs, which would leave her bruised in the morning, but Liara didn't care anymore as another orgasm shook her to the core.

Time lost meaning. There was only her, and Shepard and her tongue. Orgasm after orgasm seized Liara, and she was further embarrassed by how wanton her moans were, how easily she was pushed to the edge of climax, how evident her arousal was. It might have been hours, or minutes, but some part of her registered that she wanted… needed more and her protests turned to pleas.

"More… Please, Shep…" She sobbed, barely able to support her own weight anymore, her arms trembled. "I need…"

Abruptly, her lover stopped and straightened. She felt one of Shepard's hands on her hip, the other on the small of her back. "What do you want, my girl?"

Goddess. Shepard wouldn't make her ask. Not this. Shepard liked to hear Liara beg for things, beg for her to grant her release, beg for her to enter her,to touch her. It aroused her partner to know she held that sort of power, to know that Liara wanted her. But surely she would not make her beg for this, to give voice to what she wanted. Tears stung her eyes involuntarily. It was too humiliating, to be wanted to be taken in this way. But she needed it.

She reached out with her mind, without so much as a murmured "embrace eternity." The force of the arousal that hit her was physically overwhelming. She probed at the edges of her lover's consciousness and felt her be accepted, felt the sharp stab of lust tinged with love, with affection, with determination. The meld truly began, and she let Shepard feel her inner conflict, trying to make her see why she couldn't ask for it, to feel her shame.

A wave of calm reassurance washed over her, and she knew that Shepard understood, but there was also that determination as solid as ever. It's okay, my love… whispered in her mind, but her lover vocalized the other side of her feelings aloud. "Tell me, Liara." The tip of the shaft that Shepard wore eased between her cheeks but ventured no further.

I can't…

You will.

Tears of frustration slipped through her eyelashes, and she gritted her teeth. The ache between her legs was too fierce to resist. The last of her willpower ebbed, and she felt her shoulders relax in submission. "Please… please, Shepard fuck me…" She cried through gritted teeth, hoping, though she knew it wasn't enough. "…please fuck my ass. I need…"

"Touch yourself." Shepard grunted. The length of the shaft entered her, slowly at first as not to hurt her, but then more aggressively. Liara complied, reaching back with one of her hands to graze her clit. The first orgasm was immediate and powerful.

Hands gripped her hips, pulling her back onto the shaft, into her lover's groin. The physical sensation combined with the shared emotions rendered the world irrelevant. There was nothing but pleasure, nothing but feeling. Each orgasm from that point on was shared, and the two cried out collectively in one voice. Without realizing, Liara spurred her lover on, begging her for more, needing to feel both of them cum again… and again.

Until neither body could sustain anymore, until too much pleasure became pain and the couple collapsed together. It was several hampered breaths before either of them moved. They had fallen on their sides, with Shepard still fully embedded in Liara, her arm cast about her midsection. Pulses slowed, and Liara basked in the warm, soothing feelings she received from her lover. Affection… adoration… understanding… and above all love. Love as powerful and aching as sorrow. Emotions wrapped around her, enveloping the Asari in safe comfort.

Eventually, the human gingerly pulled out of her lover and removed the toy from herself, tossing it aside carelessly so she could fully snuggle against her. "Shepard…" Liara felt herself blush again, convinced she would be permanently purple.

"Shhh…" The human gently stroked Liara's crest, pressed a gentle kiss to the back of her neck. "It's okay. Although the extranet was a little… vague as to how sensitive you would be."

Liara tried to distance herself from the burning in her cheeks through clinical explanation. "Purebloods have different sensitivies. Or nerve clusters around the anus are more concentrated—" She yelped as Shepard smacked her bare backside with her palm.

"Why didn't you tell me?"

"It's… it's not common sexual practice among the Asari. It's even frowned upon." Liara rubbed the stinging from her rear. "And you're not the only one who can do research, Commander. It's equally, if not more so, taboo among your species."

"No more taboo than anything else we've done." Shepard whispered and treated her to a barrage of images, of past sexual encounters across their still-active bond.

Liara sucked in a breath at the charge of arousal she received from each of the images. "Yes, but—"

"But nothing, my love." Shepard nuzzled into her neck and placed a few dainty kisses along her crest. "You never have anything to be ashamed of with me."

Liara relaxed into her lover's touch, and felt as well as heard the sincerity of the words. "I didn't know you would… enjoy it so much."

The commander scoffed quietly. "Please. As if you didn't know anything that lets me take you and make you mine wouldn't get my rocks off?"

The exhaustion from their encounter combined with Shepard's gentle caresses lulled Liara towards sleep, which she was helpless to resist. A part of her, the scientist part, made mental note to research the human expression of "rocks off" before slumber claimed her.

And... there you have it. Leave me your thoughts.