Summary: Thane/Kasumi. When underwear starts to mystically disappear from their quarters, Thane takes on the case of finding the one responsible. masskink prompt. E rating. Oneshot.

So many thanks to my new beta: Laufeyson'sWife - u/4205251/

Original Prompt: . ?thread=41665364#t41665364

Kasumi has a bad habit of going around stealing the crew's underwear. Eventually Kasumi gets caught red handed.

.-oOo-.

He wasn't exactly sure when it started, or when he noticed the first time. By the third or fourth pair of missing underwear however, Thane decided it was time to do something about it. He was a neat man, in control, everything he owned was just where he intended them to be. It was a part of his training. Leave no trace, keep your eyes peeled, know when you've been having unwelcome guests, and he was certain he'd been having unwelcome guests now.

It was just a matter of observing the crew to figure out who broke into his quarters when he wasn't there. No one seemed to exhibit any unusual patterns at first, but then they were an unusual bunch to start with. For over a week he traced his top candidates in their doings on the ship. With subtlety, of course. No need to have any one of them start asking questions.

It wasn't until he was laying in one of the ducts over the starboard lounge, watching miss Goto read one of her books, that he found his first clue. It was nice to get to move and stretch his limbs after lying in the tight space for a few hours, when the woman got up and disappeared into one of the ducts by the farthest wall. Waiting didn't bother him any more. He could sit in wait for his target hours on end without giving up, without making a sound, without being detected. The skill was many years in the making, but now he had perfected it.

Thane knew most every nook and cranny of the Normandy. Survival one-o-one. Know your surroundings. It had been one of his first priorities when he boarded the ship and entered the service of Commander Shepard. That was why he took his time while maneuvering backwards through the cramped space. Took a right, past one of the big fans, and lingered around the corner a few meters from where he could hear the woman work her way through the ship.

She was good, he had to admit, silent, and he couldn't find any other trace of her when he followed on a respectful distance.

When she stopped inside a grate by the floor in the Yeoman's chambers, Thane moved around to be able to watch the room from another angle. He saw her crawl out of the wall and make her way over to a dresser. It was obvious from the way she moved that she had been here before.

Apparently Thane hadn't been the only one getting secret calls to his personal wardrobe. Miss Goto was browsing through the small flimsy clothes in a carefree manner. Holding up a few of them, discarding others, and Thane had to agree, the Yeoman had some interesting tastes when it came to delicates.

After a while the thief tucked her prize inside a hidden pocket and made her way back into the duct again, checking the room to make sure nothing looked disturbed before closing the hatch behind her. Thane followed her back to her room, watching how she hid her newest acquisition in a box under the bed.

Now was just the question of what to do with this information. He could tell the Commander, of course. He could confront the thief on his own, or simply steal back what she had taken and return them to their rightful owners. Wouldn't be too hard to figure out what belonged to whom.

In the end he didn't do any of that. There was something very naughty, but terribly innocent, in the way the thief went about her hobby, and the drell came to watch several of her heists in the following weeks. Not only did he enjoy the challenge of following her without her knowledge, but he came to appreciate her technique. The different ways she lured herself into someone's quarters. Sometimes with a simple cloak and slide through a closing door. Sometimes through the ducts. Sometimes, and this had Thane's heart rate spike every time she did it, with the owner in question in the room with her. Idly keeping the conversation up and quickly picking a pair while his or hers back was turned. The boldness of it had him liking her even more.

And he had to admit to himself that he liked watching her work. It was exiting on an otherwise rather long and uneventful trip through the stars. Going down planet-side to fight along Commander Shepard had its appeal too, but it wasn't exactly what he loved the most. Their work was too open, too head on, too much shooting and chaos to get to their objective. Thane preferred a finer touch on his missions, even as he understood the need for the violence in most cases.

One night he visited Miss Goto's quarters when he knew she was out. In the dark he went through the box of underthings she had stolen. Delicates in all kinds of different colors and shapes. A flimsy, black number that must cover so little of the bearer it had to below to the Yeoman. The young woman seemed to have a very specific, and fairly daring, taste. He also found a pair of boxers with bold blue and red stripes together with a red star. He recognized the patterns to belong to a Captain America, a comic book hero Jacob had told him about. Maybe they were his?

He found his own belongings among the clothes, but didn't take them. She couldn't know he had been here. The last couple of days Thane had played with the idea to apprehend her during one of her secret visits. It could be fun to see what she'd do getting caught, and this game was all about fun. To that end he paused before her wardrobe before leaving the room. Swiftly picking out a pair of pink and white striped panties. They fit her and the girlish soul that lay beneath her hood and he hoped he'd be able to give them back to her soon.

Two days later the perfect opportunity presented itself. The sneaky woman had positioned herself in the XO Lawson's quarters and Thane knew the genetically enhanced woman wouldn't be back for a few hours, being down on the station they were orbiting with Shepard.

Feeling how his chest tightened in excitement he dropped down on silent feet from the duct in the ceiling and soundlessly made his way up behind the thief. Successfully standing against her back, one inch from touching, the rush of pride filled him. Either she must be more invested in going through the drawer than Thane thought, or he had overestimated her skill. She should have noticed him by now.

"What are you doing?" Thane let his voice vibrate low and calm on the side of her head. He had never understood her choice of using a hood, it worked well in covering her identity, but also severely limited her field of vision.

Miss Goto startled so hard her body jumped a few inches off the floor and simultaneously dropped the piece of clothing she had been studying.

Yes, this did make him smirk. It was a guilty pleasure of his, one he would never admit to, but just the same, he loved sneaking up on people.

The long strand of curses that escaped the thief's mouth was in a foreign language to him. But it didn't sound very nice.

"Thane," she said as she tried to catch her breath, still not turning around to face him. His proximity to her made that impossible, pinned between him and the dresser. "You scared me half to death."

"My apologies," he murmured. "I was just so surprised to find you in here. Did you know the door is locked from the outside?"

Miss Goto cleared her throat.

"Maybe," she said in her soft, sing song voice, regaining her composure fast.

"I'm fairly certain that is meant to keep prying... fingers... out?" He leaned in on her, his chest touching her back gently and placed his hands on the dresser, closing the pulled out drawer with a thumb.

"And still..." She tilted her head, studying his hands. "I don't seem to be the only one intruding."

"Someone had to make sure no more delicates disappeared on this ship." Adding some threat into the voice made it coarse and vibrate through his chest. He felt the shiver running down from her shoulders, taking half a step forward so they stood pressed together, body against body.

This had been a chase, a long time coming. Thane felt it to be only fair to enjoy the capture, making her a bit uncomfortable, maybe flushed. He loved to tease. But he wanted to see her face.

"Are you going to report me to the Commander?" she asked, her muscles tense against him.

"That depends." Thane slowly pulled the hood back over her head with one hand. It fell in creases around her shoulders. Finally her face was revealed to him. It was flushed with a soft peach color on the cheek and along the neck, dipping down under her clothes. He wondered briefly how long the blush would stretch. Black waves of hair ran like silken waterfalls from her head and the drell couldn't keep from carefully turning his face into it and inhaling her smell. Met with scent of citrus and something more, something earthy and very feminine, he let his lips grace her ear with feathered touches. "Are you going to stop stealing?"

The shiver that ran through her this time couldn't be denied. He felt it, and what was more, he smelled it. Arousal lingered around her, wafting up through her skin and invading his nose.

Mission accomplished, he chuckled for himself and was just about to step back from her when her hips very deliberately rolled and ground her bottom into his crotch. Oh, uhm... that wasn't exactly what he had in mind when he started this. But his body didn't seem to care as he felt things stiffening in his pants.

"I don't know," Kasumi said melodiously, turning around when he took a respectful step back.

He hadn't meant to force himself onto her, he just enjoyed the teasing, but he'd never lay a hand on her without her outspoken consent.

"That depends... Maybe you could convince me?" The woman let her hips swing seductively as she walked after him.

Thane's throat went dry in an instant. No, this was not a part of the plan, and yet, he couldn't seem to move when she stopped in front of him, tightly tucked into his front. The heat of her body penetrated his leather clothes, making him want to squirm. He didn't, keeping his trained face in a cool, detached mask.

Miss Goto's thin fingers flattened on his chest, palming up over it. Her face was an enigma, the same flirtatious smile as always present on her lips.

"No?" she pouted excessively before biting her lower lip teasingly, the soft flesh straining under her teeth. Thane had a hard time tearing his eyes away from it. The slight rub against him when she shifted from one foot to the other made blood flood in a downward trajectory.

When one of her index-fingers gently traced the bottom of his sensitive frill he realized he had to act. She was in control and she knew it, and that wouldn't do.

Gripping her hips roughly, he forced her back against the dresser. Her rear hit the piece of furniture, and he held her there. Kasumi gasped, taken by surprise from his sudden moves. Thane pressed himself against her, towering over her, lips drawn in a thin line. He was almost ashamed of how good it felt to have her soft body so close. But he pressed the instinct back at once. He didn't betray anyone by doing this, he didn't have any ties to anyone anymore. And yet every time he took a partner to bed the spirit of his dead wife had to come visit, if only briefly. It would probably be like that for the rest of his life, but he couldn't let it interfere with living it and he wanted to live it, right this second.

"You really want me to?" he asked more forcefully than he intended to.

A smile spread on her face, and her dark eyes met his, inches away.

"Yes," she breathed.

A deep, soft moan rumbled out of him when he plunged his lips down on top of hers. Quickly tasting her, letting his tongue writhe together with it's partner in their mouths. He pushed his hips into her, finally letting go of his tightly held control, glorying in the friction caused by his pants.

Hands traveled up and down their bodies, the two moving, rubbing, reconnecting in a heated struggle for more. He palmed her breast, she cupped his crotch, making him bite down on her lip, sucking on it as he thrust a knee between her legs, grinding her down on it. Kasumi moaned into his mouth.

Little by little their clothes shed away, greens and pinks contrasting over each other. Thane tore his lips away from hers and started littering her neck with kisses, down her collarbone. He cupped one of her breasts and scraped his teeth against the bulge it formed in his hand. She arched in his grip and clawed his back before delving her hands down to his leather pants, quickly undoing the buckles.

Kasumi gasped.

"Thane," she said and looked down on him, eyes big in surprise and maybe a bit of amusement.

"Someone kept stealing my underwear," he smirked at her, grabbing both her wrists and guiding the small hands in between his legs to touch his nakedness.

She laughed, a clear, melodious sound, and gripped him, her fingers closing around his length.

"Mmh," he hummed. Her fingers were cold, but they felt nice, rubbing up and down, squeezing. He pushed her suit down from her hips, taking her panties with it while she was distracted with caressing him. "Very nice." Grabbing both her thighs from behind, he heaved her up onto the edge of the dresser to be able to spread her legs, a green hand shooting in between them.

A clear, throaty gasp was teased out of her when he slipped one finger into her wetness, letting it get good and moist before searching his way up on her sex to find that spot where human women tended to like getting touched.

Kasumi whimpered and her hands faltered in their movements, hips rolling tiny circles to get more from his hands.

"Yes, nice," she agreed, closing her eyes.

Thane teased her opening, not quite slipping in before going back up, watching her intently as the thief leaned back on her hands, concentrating on the sensations he pressed through her body. Biting her lip, she groaned impatiently, pushing her pelvis forward, hunting for his fingers.

"Ah-ah," Thane said tauntingly. "This is what girls who steal get." He brushed his lips against her neck, drawing in the intoxicating smell of her hair, slowly losing the small amount of control he had on himself. His body was screaming for her every time she gyrated on top of the furniture. Every time her breath caught in her throat because of something he did.

"Do you want more?" he breathed next to her ear, his voice low with lust.

"Yes," Kasumi responded at once, a hint of desperation in her voice.

"Do you promise to be a good girl?" Thane pressed with his fused middle fingers against her opening, letting them spread her without really going in.

Kasumi bit her lip, but didn't answer, her eyes still closed.

"Well? Do you?" he asked, tracing the shape of her ear with his tongue, pressing his fingers tantalizingly slowly into her. His other hand's fingers kept busy with rubbing circles around her most sensitive spot. Faster and faster. Each heaving breath from her pushed out chest coming out in small begging noises.

It was starting to drive the drell mad. He needed her now. Please? Couldn't she just relent so they could get on with this? When she didn't answer he slowly withdrew his lower hand. That got her attention.

"Yes, please," she squealed. "I'll be good, just... please."

Thank all the gods above.

Kasumi cried out when he drove his fingers into her. Keeping up the incessant rubbing on her sex as he let them dive in and out, hard fast strokes, curling his fingers when they got the deepest. He felt her walls contracting around him, almost hard enough that he was pushed out. One of Kasumi's hands came up to squeeze his shoulder, her nails digging into his scales.

A strange curse was drawn out of her as she came down from her high.

"Oh God, Thane," she panted.

The green assassin didn't intend to give her any rest. He pushed his pants down just enough before grabbing her thighs hard, positioning himself between them properly and driving into her.

Now it was his turn to groan. The feeling of her soft and warm insides flooded his nerves with stimulation. With a hand on the small of her back he tilted her just so, the other nestling into the nape of her neck, forcing her head forward to crush their mouths together. It was all fiery passion as he finally let himself go, giving over the reigns to his body and instincts.

The woman gasped for breath as he went in deep, grinding their hips together for a moment, feeling how she flexed around him, before going all the way out only to slam into her again. Her fingers gripped his shoulders hard and he had to hold her still from sliding back from the edge with each long, firm thrust.

He devoured all she had to give, biting her lip, groaning against her skin as the heat, the tightness in his gut started to build.

"This... hng... is what... gh... the girls who... oh by all... abide by the rules and... mnh... don't steal other people's... ah! Underwear gets," he ground out through gritted teeth by her ear, quickly putting in words between one push into her body and the next.

Kasumi arched against him, moaning and gasping in pleasure.

"I'll remember... ah! That..." she breathed as she tried to meet him halfway with her hips.

Thane released his hold on her to slide his arms under her thighs, lifting them up, her knees hooked over his elbows, gripping her wriggling hips and taking the control from her. He wanted it, he needed it, to keep this from ending too soon.

Kasumi fell backwards, catching herself on her hands behind her back. The new position made him reach deep within her and she cried out when he drove into her again.

"Oh by all gods," Thane gasped. He had found an edge, or a tighter passage, or something that felt unbelievably good.

Closing his eyes to concentrate on the feeling of it rubbing just right over his length, he started moving faster, building up the fire in his gut to a roaring inferno, and he couldn't stop. He pounded into her as Kasumi whispered out encouragement with bated breath, oh please, don't stop, just there, I need...

And then her walls tightened around him, drawing a guttural moan out of him as he kept up the hard and punishing pace, the overload of pleasure blinding him when he tried to look down on her. Feeling his muscles jerk and then burying himself as deep as he could go, the intensity of the waves slowly ebbed down into a bearable level.

When he could finally see again, he focused on the face inches from his own. They shared the air between them, panting hard in the aftermath. Thane's lungs burned slightly from the excretion, but he ignored it and planted a soft kiss on her flushed lips before slowly untangling himself from the woman.

"Wow... Thane..." Kasumi sat up on the dresser and watched as he hosted his pants back up onto his hips. "You almost made me consider going straight." That flirtatious smirk spread on her lips again and she jumped down to gather her clothes.

"Only almost?" he asked and reached for his discarded vest.

She shrugged.

"A girl got to eat."

He chuckled, she giggled.

When both of them were dressed again and ready to go Thane reached into his back pocket.

"I thought maybe you'd want these back," he said and let her pink and white panties dangle from two fingers. The smile he gave her wasn't without it's charm.

Kasumi gaped at him and snatched the small cloth from his hand.

"You," she said, eyes shrinking into thin slits in suspicion.

"I also expect my underwear to find their way back to my room?" It wasn't really a question as much as a demand.

Kasumi gave him a crooked grin.

"Maybe," she said and backed away from him, towards an open duct by the floor.

"Maybe?" he raised both eyebrows sceptically.

"Or maybe you'll have to remind how to be a good girl." She crouched down at the duct, turning around to face him. "You never know..."

"I guess we'll see," he answered as he watched her slip into the small hole in the wall.