I don't know how it happened.

Catherine and I were just sitting next to each other, having agreed it made the most sense for us to share a pair of seats on the charter bus that was taking the whole grave team to some "mandatory training seminar" Ecklie had signed us all up for. The session was to be held in Denver, at a convention of CSIs from across the southwest, and because apparently the lab was too cheap to fly us out.

It was late, maybe one or two in the morning, but as we were all used to sleeping through the daylight hours and working through the dark ones, the bus was noisy and restless as we chattered and laughed. Nick shared a seat with Warrick, and Greg was paired up with lab tech Hodges, who'd for some reason decided he'd tag along on their little field trip. Grissom, of course, had a set of seats to himself. He'd been quietly reading some sort of etymology journal since the ride started a few hours before, with the exception of the few times he'd offered a brief interjection into the loud and often quiet passionate discussions of the others.

Again, I don't know how it happened.

Nicky, Warrick and Greggo were all leaning into the middle aisle of the bus, and seemed to be sharing some sort of highly hilarious, conspiratorial bro-talk. Hodges, after being ignored multiply by the other three, had curled up in his table-of-elements-printed snuggie and dozed off an hour or so before. She and I were just talking, going over the last few cases we'd worked, when it happened.

I don't even recall what it was she'd said, but it was some quite funny and alarmingly accurate shot at Grissom, and I doubled over with laughter, collapsing into her and covering my reddened face. She caught me easily, and we fell into an oddly comfortable embrace. I remember thinking how happy I was we'd sorted out our differences and learned to be pleasant as coworkers, even as friends; I'd always admired Catherine, and it was so much easier to handle the emotionally difficult cases knowing everyone on the team was behind me.

The guys were a few rows back, whispering and chuckling over a bag of twizzlers, and no one was paying any attention to us.

After a solid few seconds, it dawned on me that this was longer than the average hug, but I didn't move. Cath didn't either, so we just ended up softly pressed to each other, arms wrapped around waists and rocking gently with the sway of the bus over the highway. It was nice.

And that's kindof when it happened.

She's shorter, so her face was resting on my shoulder, and after a few minutes of perfectly comfortable silence I felt her lips dust over my bared collarbone. Thinking it must've been accidental, I was careful not to react to the touch, for fear of breaking this lovely, warm moment we were sharing. When it happened again a few seconds later, I was sure I must've imagined it.

Then she brushed her mouth across my skin a few more times, and I was forced to wonder if she wasn't doing it on purpose. When suddenly her tongue slipped out and the contact was definitively more than the casual touch of two friends, I stifled a gasp.

She lapped gently at my cool skin, tracing sensual circles and arcs and dipping into every sensitive hollow between my bones, and I didn't think; I just let my body react. I found myself leaning further into her, and after a bit I realize I've let free a soft sighing moan. She heard my hum of pleasure and felt my hot breathing near her ear, and took that as her cue to go a little further.

I pulled her torso even closer into mine, pressing us together. My eyes fell shut. I was astonished by how incredible she felt, how beautifully we fit together, and mmmm she really does know how to turn someone on… God.

When I made an even more audible sound of satisfaction, she smiled into my skin and began kissing wetly up my neck. It was when our lips met, finally, that it hit me: holy fuck, The Catherine Willows is touching me. Shit, maybe I should touch her too…

We were still kissing softly, gently, with no tongues when I withdrew one of my arms from around her and slipped it between us. My fingers slid up under the hem of her shirt to draw feather-light patterns on her soft stomach, and she moaned, deepening the kiss. I parted my lips easily under hers, relishing the feel of the lovely full mouth I'd so often caught my eyes lingering on as it caressed my own.

I hadn't noticed that Cath had unclasped my bra until a strap slipped off my shoulder and it fell open in the back. She drew back and looked me straight in the eyes, icy aqua meeting chocolate brown. I could tell by her expression that she was asking me if I was okay with how far this was going. I told her that yes, of course I was, by surging forward to nibble at her clavicle bone.

She giggled and slid my bra off, and after a few moments in which I was suckling and nipping at the pale shell of her ear so vigorously she found herself paralyzed with pleasure, she tugged my camisole up and over my head. Her blouse soon followed, as well as both my and her jeans and her gorgeous lacey red bra.

We teased and worshipped each other for I don't know how long, maybe an hour even; all I know is that when we saw that the boys and even Grissom had finally all fallen asleep, we threw all caution to the wind and stripped off our underwear. Trust me, it was so not easy to be quiet as none other than lab sex symbol Catherine Willows fucked me with her mouth, but somehow I managed, and we didn't wake anyone. She was less successful with controlling her noises of ecstasy than I was, but thank God, by then the others were all soundly slumbering.

So, that's how it happened.

Now it's morning, maybe 7 or 8 am, and everyone else is still asleep in their seats. I'm lying here under a thankfully very large fleece blanket, stripped down to my panties, snuggled up against Catherine Willows. I reach across her, wrapping an arm over her slender stomach, and she cuddles closer into me in her sleep with an angelic little smile.

I still don't really know how it happened, but damn am I happy it did.