The whistle had been familiar, sharp and slacking her movements still. For a moment at least. Because then she had intentionally ignored it.

"C'mon, Kate." His body was leaning onto the pliant rails of the sparring ring and she could hear some sort of mangled pleading in his tone, the nearest he would probably come to it anyhow.

Her fist landed solid into the center of the weight bag anyhow.

She wasn't in the mood to give in to him. She'd trade punches with this inanimate object rather than verbally spar with him. It was such an easy bargain to make – physically raging so that her mind didn't have to do it. And, frankly, she was just so tired of giving in to him. Over and over and over again. And it had nothing to do with the fact that he was her superior (sure fucking thought he was superior to her in every way, didn't he?). It had everything to do with the fact that he never allowed himself that same damn weakness.

Maybe she wanted to be his hero some days.

Or rather, maybe and more likely, this time she just wanted to blame him for everything.

They'd become exceptional at making each other their primary targets.

"This is stalking, Gibbs." She landed another solid swing into the bag, checking how wildly it swung away from her, forcing herself to re-position in response to its unpredictable wavering.

"If I were stalking you, Caitlin," he said it terrifyingly slowly, like a threat to her senses and intentionally designed to pull at her edges, "you'd never know it."

She couldn't let him keep winning so easily.

Because this time... this time it'd gotten someone killed.

"I'm busy."

And it'd keep getting people dead if they didn't just... stop.

"Get over here." The authoritative switch of his tone was something that usually would stir her into action, remind her that they had a job to do, a responsibility, but now... "Now."

Now it was more a reminder of how sensually deep his voice could go when he was telling her how much he loved the taste of her swilling around in his mouth.

How much he wanted to just slide his tongue inside her while his hands bruised her thighs and then stroked their apologies with an unbearable lightness.

How sweet his hands curving on her stomach and pressing lightly down could feel when he just kept his mouth going on her until she imploded.

Now it just served to remind her how he groaned in his sleep like all his realities were being choked out just before he said -

"Caitlin."

Shannon, actually.

Usually, when his voice trembled this murderously low and aching, he was talking to his dead wife in his sleep.

It was the only secret she could manage to keep from him.

Because he wouldn't forgive himself if he knew.

"You shoulda let me go in there." She finally swung away from the punching bag, letting it bump up along her back as it came her way and slump her forward as she lifted a hand in his direction. "Maybe I could have - "

"You don't get to question the choices I make." Bargaining with a bag obviously wasn't going to work because his voice said he was more than prepared to hash this out and he didn't plan to lose the argument, didn't plan to let it end without some sort of resolution that appeased him. "Casey's dead and you're still breathin'."

But not easily, she mused. Breathing should have been easier than having to gasp past fisted lungs and horrified self-reproach.

"You should have - "

"Kate." The supposedly relaxed lay of his body against the ropes disappeared and he was suddenly so much taller than her, so much larger than life and so goddamn sure that he'd made the right choice, that he'd been so very correct and satisfied in his sacrifice. "He's dead. You're not. It's an acceptable loss."

"Acceptable?! It should have been me. I could have - "

"What? Coulda what? You coulda convinced a killer not to kill somebody, Agent Profiler? Get over yourself." He said it while turning from her, loosing the words into the spacious air around them and letting them echo how darkly they were made. "Charming as you may be, sweetheart, I wasn't sending you into that room."

Screw him and his smug condescension, the very voice he used when he was fed up with fighting and he knew he could shut her down with an uncurbed tone and pointed words.

Screw him and his ability to hurt her by just speaking so slowly and pointedly, quietly.

Screw the ease with which he made her feel like she was two inches tall.

She wasn't in the mood.

"Derek Casey was a decorated agent." She threw it at him just as pointedly, as quietly. She wasn't in the mood to let him so easily win anymore. "Three kids, married twenty two years. You know that?"

"Yes, I do. He knew the risks and he was trained for exactly that situation. He was aware of the possible outcome."

"Little League coach." She accused, kept her voice hardened. "Helped Abby at the soup kitchen sometimes."

"It was an acceptable loss." The whispered tone, the lowness of his usually perfectly pitched shoulders, told her that he didn't believe a damn word of what he was saying.

That he was only saying it to try and force his head, and hers, to accept it.

Well, she couldn't just accept it this time. No matter what his reasoning was. "His death is not an acceptable result, Gibbs."

The speed with which he turned his entire body back to her was near unnatural, every inch of him riveting an anger she hadn't seen in months on months. And never directed at her, never so evenly thrown in her direction. "Your death is was not an acceptable possibility, Kate."

And there it was, really... That was his truth, wasn't it? His final explanation. His very version of fact. There wasn't a shifted variation of their world in which he ever, ever, would have let her into that room. Because she was Kate, his Kate. And she was just plainly not allowed to enter into a situation so obviously deadly while he was capable of sending someone else in her stead. She wasn't allowed alone in a place where he just couldn't see what danger might come at her from any direction.

No wonder he'd been so deliriously happy that she'd resigned from the Secret Service. Kept her from being a lamb, stupidly leaning into certain slaughter.

No wonder he'd offered her a place where he could prowl and watch whatever may threaten her.

"Your... how you feel about me as a person should have no bearing on - "

"It was his job and it got him killed." He was right, if she were to step closer to logic and farther from him. Casey had known what the job entailed, had been long aware that someday, at some obscenely surreal moment, it could end every little thing. "Accept that. You can't change it."

The fact that he had been a bravely aware man, stepping into a situation that could kill him, seemed to only fuel her guilt, her shame.

"But I could have - "

"There was nothing you could do, Kate." Gibbs grit the words quieter, blinking as he shook his head and lowered his body and suddenly he was nearer to her in this remorse. He was closer as he crouched and she could see in dulled blue eyes that he was so very angry with her, but so legitimately in love with how tightly this was twisting on her.

It was familiar to him, she assumed. Because he carried guilt with him like it was his wallet, tucked safely in a pocket and checked randomly throughout the day just to be sure it was still close to him.

His guilt, the way he wore it, held it... he hadn't necessarily realized what he had done.

It was suddenly so obvious to her. That he hadn't known he'd hidden her from danger until after another man had died as a result of choosing to keep her close rather than letting her try to talk a madman down.

He hadn't known he was doing the killing until Casey had stopped breathing.

"There was nothing you would allow me to do, Gibbs." She accused softly, shaking her head as she stepped closer into the side of the ring's foundation, letting her hands press into the floor of it near his feet.

"You're goddamn right." His voice had actually whip-cracked his anger over her sharply enough to make her flinch, her head snapping back so that she could watch him exhale into the loudness of his own sudden and shocked silence.

He'd done this (and distinctively chosen to do it, even if unconsciously).

No, correction, they'd done this. They'd managed it together, blinding themselves to consequences.

They'd signed a warrant on another agent's death the first time they'd let themselves fall into each other.

Kate blinked rapidly, shaking her head against a rise of bile tinted guilt, "We can't do this anymore."

His hand shot between the ropes and caught against her shirt with a horrifying speed, a quick but tight lightness that reminded her that no matter how big or lankly or long he was – he could quietly kill and murmur that death on her lips without remorse. He did too, jerked her hands and breasts into the flexible roping as his head leaned and his eyes glittered hard over her face just before kissing her roughly and assuredly and so strongly that she hadn't the time to catch her breath. It was the angriest kiss she'd ever felt off his lips but, somehow, it still tasted utterly of him and his adoration of her. It still had her moaning as he sighed his tongue to hers and let their mouths together in mingling sadness.

Gibbs minutely shook his head after brushing off her lips, negating her statement entirely. "Watch me."

He'd brokered a Devil's Deal long before deciding another agent should take her place, possibly the first time he'd dropped her into his bed and licked along her collarbone.

He'd bargained another man's death for her life and disregarded his guilt in doing so (tried to anyhow).

She could taste the leftover bitterness of that sacrifice on her lips, even as his other hand gripped into her hair and stilled her argument.

They'd signed this deal together, really.

Shared guilt was both punishment and reward.

"Just watch me."