Title: A Little Experiment
By: reversedsam
Pairing: Cath/Sara
Fandom: CSI: Vegas
Rating: NC-17
Disclaimers: They're not mine, but I promise I'll have them back by midnight.
A/N: All mistakes and British spellings are mine.
Summary: Catherine has a theory she needs to test.

***

"Hey Sara, you busy? Any chance you can help me out with a little experiment?"

Looking up from my magazine I see Catherine standing at the break room door.

"Sure, what do you need?"

"Just your body." She flashes me a smile. "Preferably in lay out room four."

I return her smile as I stand and walk towards her. "Lead the way."

"So what are we doing?" I ask as we enter they lay out room, there's a crash mat in the far corner that immediately gets my attention.

"Well." She starts, gesturing for me to follow her to the other side of the room. "My latest case. Female vic, mid-twenties, found in a store room at a club, COD was massive head trauma. Although the original call out was for arson, police discovered the db while making sure the scene was clear."

"Right. I'm not seeing how this ends in me landing on that crash mat though." I smirk, she may not have said it, but I'm sure that's what going to happen.

"I'm getting there." She smiles. "We originally thought the arson was an attempt to burn the body, along with any evidence, but it didn't fit. Fire was started at the opposite end of the club. Then our suspect handed herself in."

"She confessed?"

"Yes, but to accidental death, she was distraught when she got here. She says that she and the vic, her girlfriend, were going at it in the store room."

"Going at it how? Fighting? Or a completely different form of physicality?"

"Option two. Vic did have a hickey or two but we couldn't get DNA because the sprinkler system went off shortly after the fire alarm."

"Washed away the evidence." I offer. "I hate it when that happens."

"Exactly. So, long story short, they're getting into it and our suspect says she was backed up on the wall, pushed forward; they lost their footing and fell backward. Vic hit the base of her skull on the corner of an empty crate. Suspect says she ran for help as soon as she saw the blood, unfortunately for her, she ran straight into a crowd of people panicking about the fire and trying to get out of the building."

"So nobody was paying attention."

"Right, police were so busy clearing the scene that it wasn't until they found the body that someone actually listened to her."

"And still I don't see how this end with me on a crash mat." I joke.

"Ah well, the vic had various marks, around her wrists, scratches on her sides. That type of thing. So I got an account of what happened from the suspect, as best as she could remember. Now I need to make sure it's possible." She grins. "It all fits, but you know we have to double check."

"So, a little re-enactment?"

"Got it in one, and lucky for you, you're around the same height as our vic."

"Lucky me. And let me guess, you're around the suspects high?" I ask, raising my eye brown.

"Convenient isn't it?" She smirks.

"Very. So where do you want me?"

She raises her eyebrow and flashes me a smile, a slightly feral smile and I immediately feel like her prey. So much so I'm immensely grateful when she starts talking again.

"I've taped off an area the size of the store room. We can't use the actual scene as it hasn't been cleared yet. The mat is obviously because I don't want us injured. I've also marked on the mat the exact placement of the crate, so when we fall, if you're head isn't were the mark is, we know she's lying."

"When we fall?" Now this wasn't part of the plan. If I've got this right, the end result will be me on my back and Catherine on top of me. Okay, so I've thought about that situation once or twice. Usually minus the crash mat, minus clothes and plus a big comfy bed. I hope Catherine doesn't want much input from me on this, I have a feeling my brain won't be at full capacity soon.

"Yeah, now come on."

She walks to the far wall. "Right, suspect said she was pushed against the wall as soon as they entered the room." She stops for a second, looking at her set-up then places herself against the wall not for from where the door would be. "So they'd be around here."

"Looks right." I offer. I haven't moved yet. I can't believe I have to act this out with her.

"Well come on then, shift ends in three hours, I'd like to leave on time." She teases, holding her hand out to me.

"Right, sorry."

As soon as I'm within reach Catherine grabs my hips and pulls me flush against her. Well shit. Deep breath Sara, just try not to think about it. Try not to think of how good her body feels pressed tightly against yours. Yeah, best not to think about that.

"One second." I tell her as I take a step back and shrug off my jacket. Surprisingly I'm feeling a little warm. I resume my earlier position and feel her hands on my hips again. I will my body not to respond as they slowly slide around my hips to rest just above my ass. Relaxing into the position, she lets her head fall back to rest on the wall. Also best not to think about now damn sexy she looks right now.

My hands have remained by my sides. I have no idea if I'll have the self-control to stop them wondering if I touch her right now.

So I settle for placing them on the wall either side of her head. She looks delicious from this vantage point. My height advantage gives me a lovely view of her cleavage, a view I'm absolutely going to ignore. Really, I am.

"So erm, what now?" I ask, trying to distract myself from the intimacy of our current position and how much I'm enjoying it.

With a grin she tightens her hold on me and in a move I'm not expecting she pushes forward and reverses our positions. I hit the wall with a slight thud. My hands are behind her head now, forearms resting on her shoulders and I want to tangle my fingers in her hair and pull her in for a kiss.

"That's what happened next." She grins. "We're closer to the crate so it looks like we're on track. Now to explain some of the marks we found on the vic."

"Bruises?"

"Not as such, reddening mostly, a few scratches too. Doc Robbins said it was all very recent."

I stand motionless and try not to even breathe as her hands gently slide up my sides. Once she reaches my shoulders she moves them forward, along my arms, leaving goose bumps in her wake. She stops when she can grab my hands with hers.

Once again I get no warning as she takes my hands and pushes them into the wall above my head. Jesus. It takes every single ounce of self-control not to moan. My body automatically tries to arch into her. This is the same position she had me in in a rather vivid dream I had a few nights ago. Okay, let's add that to the list of things I'm not thinking about right now.

She holds my wrists with her hands, her grip tight. "Struggle a bit." She tells me. Is she crazy, why in the hell would I want to struggle? Ah yes, because this is work.

I do as asked. "Wouldn't be that hard to get free, but then in that situation I'm assuming she wouldn't be trying that hard." I know if this were for real I sure as hell wouldn't.

She nods and looks up at her hands. I feel her move so she's holdings both my wrists with her right hand. "That's better; if I pressed hard enough on your wrists as you struggled I'd leave a mark. A mark consistent with our vics."

I expect her to release my hands but she doesn't. And once again I'm fighting my body's reaction as her left hand trails down my arm and side, coming to settle at my hip once more.

She has a positively mischievous look on her face and I swear she's teasing me. Enjoying the torture she isn't even aware she's putting me through.

"We found scratches on the victim's side." As she talks her hand slides higher and there's no way I can stop my breath hitching as it slips under my shirt. What the hell? Okay, maybe I was mistaken about her not knowing what she's putting me through.

She keeps eye contact as her hand moves higher. Stopping halfway up my side. "Around here." She adds as her hand moves back down, lightly scraping her nails across my skin as she goes. Oh my good god.

I try to stifle the moan, I really do. But I'm only partially successful, so I half squeak half moan at her touch. I couldn't stop myself arching into her, however hard I tried.

"Catherine? What are you doing?" I question. My voice decidedly lower than normal.

She lifts my shirt slightly to examine the faint marks she's left on my skin. Then gives me a sly grin. "Re-enacting." She replies, giving me an innocent look. Oh yeah, She knows exactly what she's doing.

I'm biting my bottom lip, hoping the slight pain will help focus my mind, but it doesn't seem to be working.

Finally my hands are released and I rest them on her hips to steady myself. "Any more marks?" I ask. Trying to sound neutral. If she wants to play. Let's play.

She's looking right at me and when she speaks, the sound of her voice sends shivers down my spine. "One more." She purrs. I feel her moving a little and freeze in place as her leg slides between mine. Jesus Christ.

My only reply is a very intelligent. "Oh god." Which I hiss out as Catherine tightens her hold on my hips and rocks me against her thigh.

There is no way I'm letting her have all the fun here. So, Using the strength I have left I reverse our positions once more. Not two seconds later I wish I'd stayed put as I feel her leg come up to hook around my thigh.

She breathing harder now. Her eyes are flicking from my chest to my mouth. And this new position means the lower half of her body is pushing into mine, making sure I'm breathing harder too.

"Last mark was on the back of the vics thigh, apparently done by a heel, vic was wearing a skirt." Her voice is low and sexy as she talks and she reiterates her point by lightly digging her heel into the back of my thigh and moving it downward.

Without even thinking I hook my hand around her thigh, keeping her leg in place, not wanting to lose the contact. Her hands move to the back of my neck as she finally lifts her eyes to mine.

I want to say something, ask her if she wants this. Anything, but I'm scared of breaking the moment.

Obviously Catherine doesn't share my indecision. With one last look at my mouth moves forward and captures my lips in a searing kiss.

I feel myself pushing her harder against the wall, wanting to feel more of her against me. Her hands tangle in my hair and my knees almost give out when I hear her moan slightly.

She gently bites my bottom lip before her tongue slides into my mouth. Fuck can she kiss.

One of her hands slides down to cup my breast and when her thumb passes over my nipple I tear my lips away from her with a moan and take a few steps back. I had to stop or I'd have taken her there and then. My body almost exploded when she ran her thumb over my nipple.

The lab is filled with the sound of our laboured breathing. And looking at her I see her eyes are dark. "Not here." I manage to tell her.

A few minutes pass as we get our breath back to normal and I try to get my hormones under control. I can't keep my eyes off Catherine, which isn't helping with the hormone situation.

"You planned that didn't you?" I ask with a smirk. I had to ask, she had to know what she was doing to me.

She gives me a sly grin before pushing off the wall and walking to me. "I figured I had to do something so you'd make a move." She shrugs. "I got tired of waiting around."

I knew it. "Asking me out would have worked you know." I smile. I have officially just been had.

"But that wouldn't have been nearly as much fun now would it? That was some kiss."

Well, I can't argue with her there.

I'm about to agree when she brings her hands up to my shoulders and pushes me back. I land with a thud on the crash matt. "What the fuck?"

"I'll make it up to you." She smiles. "But look." She kneels down next to me and points to the matt. I lift my head and turn to look.

"You were a good few feet away from the wall and when I pushed you your head landed where the crate would have been."

"Suspect was lying, if they'd have fallen as they pushed off the wall they'd have landed before the crate."

"Yeah. See, now aren't you glad we did this little experiment?" She smirks.

"For more than one reason." I grin.

"Now if you'll excuse me, I have a case to solve." She smiles before leaning down to give me a quick kiss. "After shift. You. Me. My place. We have unfinished business."

And with that she's gone. Leaving me staring at the ceiling with a huge smile on my face.

***