Author's note: This is a short one-shot companion to my story "Adrenaline" (any reader of that story will see precisely where it fits in!) However, it is most definitely also capable of being a stand-alone. This story is rated "T" for implied sexual situations, though no harsh languages or explicit sexual scenes are described.

Hope you enjoy it!

"At night I wake up

With the sheets soaking wet

And a freight train running through the middle of my head

Only you can cool my desire

Oooh I'm on fire..."

- Bruce Springsteen, "I'm on Fire"

For the past five months, he's had the same dream.

Without fail, every morning he wakes up in a tangle of bedsheets wrapped around his limbs, hair stuck to the top of his head by a fine layer of sweat across his brow. His first instinct is to the check the spot beside him, the place where lovers or girlfriends or wives should go, but it is always empty, and he is always alone.

"Take me upstairs," she whispers to him, and any form of self-control he still had breaks in that moment. Looking down into her eyes then, between fevered kisses and passionate embraces, he ceases to be Dr. Spencer Reid, Supervisory Special Agent for the FBI, and becomes simply a man, a man pressed up against the beautiful woman in his arms.

He nods, almost imperceptibly, and with that, she crashes her lips against his, even harder than before. He is lost in the moment, suddenly becoming solely devoted to the new task at hand. He takes her face into his hands once more, pressing his open mouth even harder against hers. Her hands settle around his waist, one of them twisting into the fabric of his shirt as the other snakes up along the bare skin protecting his spine. He gasps, breaking their kiss, but before he can react further, she's brought her mouth up to his again, all the while slowly moving them to the foot of the stairs and closer to their eventual goal.

He dreams of her, of her pressed up against him, of her in his arms, of her hands scratching across his skin as moves above her, his forehead pressed down into the space between her chin and her chest. He can feel her hands tangle in his hair, the sweat between the two layers of their skin, the goosebumps that rise up as she breathes in and out next to his ear. Every night, the scenes are all the same, a cruel trick played by an eidetic memory that wreaks havoc with him even in sleep.

She pushes him up against the wall with a significant amount of force, and he gasps instinctively as his tailbone strikes first, absorbing the impact all in one go. He knows he should feel pain or at least discomfort from this sudden and violent assault on this somewhat delicate area, but all he can feel now is the pleasure and the euphoria brought on by her touch, brought on by the sheer feeling of her in his arms.

"Touch me," she says, and he knows it is nothing else but an order, a demand for physical attention. Up to this point, he's been much too flustered and overwhelmed to be anything but a pliable plaything, a living and breathing ragdoll in her arms.

Slowly, with great care and concentration, he drops his hands from her face and slides them across her hips, much as she had done for him. The similarities between their actions end there, however, as he moves one hand higher, sliding it below her shirt as he slowly caresses the soft flesh of her stomach. The other hand, more daring that its counterpart, drops down below the line of her hips, playing dangerously with the skin along the border between her pants and her skin.

He wishes he could dream of something else. Something, anything, whatever – it really doesn't matter, as long as it ceases to be this one dream in particular. Every night, when he revisits the biggest lapse in judgement he's ever had, he can't help but fall into the same trap every time. He knows now that there is no permutation of this particular set of circumstances that would have resulted in anything but what had happened that night. In all the possible parallel and alternate universes that could potentially exist, he knows that there is not one single one that wouldn't end with him sleeping with one of his best friends.

Now whether he finds this conclusion comforting or not, is the real question.

They've somehow reached the bedroom, now, and he finds himself careening backwards suddenly as her hands push him down towards the bed. There's something about that action, something about the harshness of that movement that strikes a chord within him, activating something deep and primal deep down that he's never experienced before.

Without warning, he takes her by the shoulders and flips her onto her back. It is now her turn to gasp as she watches him go from dominated to dominant in an instant, instinct taking over control. He pins her wrists above her head as he kisses her, causing her to squirm in delighted agony. He pulls her shirt off as she pulls off his, and suddenly, all articles of apparel are suddenly gone, including his mismatched gray and purple socks. She murmurs absurdities into his ear, words without meaning or sense, spurred on by the simple need to speak, to communicate, to be heard – by him and him alone.

He wishes, most of all, that he knew why she doesn't ever leave him; why, five months after she disappeared out of his bed and out of his life, why he can't ever get her out of his mind.

He stops, quite abruptly, as he spots the tears behind her eyes and the moisture on her skin. Suddenly, the full ramifications of what they are doing hits him with the force of a lightning bolt, a sudden sinking realization that they, two FBI agents and close friends, are naked together in his bed. He feels shameful and guilty, as if they have instantaneously betrayed everything they had ever had before.

"Do you want us – me – to stop?" he asks her, looking into her eyes. Part of him wants her to say yes, to tell him what they are doing is oh-so-wrong, to tell him that this could never and would never happen.

But that doesn't happen.

Instead, she whispers an almost inaudible "no", moving her hips up to meet his, joining them together at long last. He moans involuntarily, jolting out of his frozen state, and even with his IQ of 187 behind him, he becomes unable to form or process any coherent thought at all. He is lost within her, and within the moment, and he can think of nothing else but right here and right now.

Every time he thinks of her, he's set on fire. And he wonders if it'll ever stop.