A/N: One shot based on 5x21 synopsis, so if you don't want to be spoiled, don't read. Please read and review!

Disclaimer: Don't own Castle.

"Beckett, don't move!" Despite herself and the dangerous situation she now found herself in, Kate Beckett couldn't help but roll her eyes at her partner's warning. Maybe it would've been cute if it weren't the forty-seventh time he'd reminded her.

"Trust me, Castle, it's not that I want to," she sighed in response, feeling the throbbing pain along her feet, her shins, her quads...both her legs screamed in agony.

"You've been doing so good even though it's been-" He paused, checking his watch, "one hour and twenty four minutes. You know, I'm pretty sure they'll think of something soon. Aren't some of the bomb squad people your friends?"

"It's not because they're friends, Castle. They'll figure something out because it's their job and they're good at it. It doesn't matter who the victim is." Sometimes Beckett forgot that Castle lived in a world where people bent over backwards for him because he was a famous novelist with a sizable bank account.

"Yeah, you're right. I'm sorry. It's just that the sooner they get you out of here, the sooner I can relax." He gave her a tight-lipped smile and carefully squeezed her hand.

"You don't have to stay, you know. Like you said, they'll think of something soon. Why don't you go out and work with Ryan and Espo?" Beckett hoped her voice was braver out loud than it felt in her head. In truth, she didn't want to be left alone, with nothing but a pressure bomb for company, but she didn't want to put Castle in danger also.

"Yes I do, Kate. You would do the same for me." He kissed the top of her head, not risking anything more intimate. If she even shifted her legs, the bomb would go off.

"Yeah, probably," she teased, remembering the time she said that after he rescued her from their sinking car. Castle deflated ever so slightly and she realized that the seriousness of the situation made it hard for him to have his usual sense of humor.

"You know I would do it for you. Always. I've had your back since the beginning." He smiled at her words...and then a twinkle, that familiar glimmer that appeared only for her, came into his eyes.

"Beckett, I didn't know you fell for me all the way back then! I thought you hated me!" His tone was light as he desperately tried to ease the tension that cruelly permeated the air. He'd seen her grimace in pain more than once just in this conversation alone and he realized the tremendous struggle it must be to stand so still for so long.

"Having your back and falling for you are two very different things," Beckett gasped, biting back tears. If only she could rest her legs (God they felt like jelly-how they were supporting her weight was beyond her comprehension). "And if I remember everything correct, it was you that fell for me in the beginning."

Oh. So THAT was how it was going to be, Castle thought. But it was something. It was enough to distract the both of them, if only for a moment.

"So you're telling me that you just let me follow you around for all that time without feeling anything?" His eyes were bright with amusement. "I find that hard to believe."

"Well, you're telling me that you ACTUALLY needed to shadow me for research when you'd already written like twenty six bestsellers," Beckett retorted, playing into the little game.

"I dunno, Kate, I think you were a little jealous when you found out you weren't my first muse."

"Yeah, well at least I wasn't jealous enough to haze a newer writer in a poker game!"

"You were a big fan of my work before we even met. You can't tell me that you weren't attracted to me on at least one level because of that." He smirked, relishing his victory.

"I would've loved those books even if they were written by a wrinkled eighty year old grandmother!" There was silence for a few minutes as they both became lost in their thoughts...thoughts much deeper than the ones brought to the surface by a silly argument.

"You know, I should've told you sooner. I shouldn't have waited until it was possibly my last chance." Castle was the first to break the quiet. "I would've regretted it for the rest of my life if it had been." He closed his eyes, seeing the cemetery, the green grass suddenly turning red and sticky, the gloved hand that reached for him, the solitary tear that slid down her face, the faintest hint of a smile before her eyes closed.

"But it wasn't," Beckett reminded him, smiling faintly. "And I regretted not going to the Hamptons with you that one summer. You know, I was just about to accept your invitation when Gina showed up."

"Really?" Castle had never heard that before. Guilt washed over him.

"Yeah, really. But I don't regret it now. We're together and that's all that matters, right?" He nodded, still kicking himself over his sheer stupidity that summer.

"But...that also means you'd fallen for me by then," Castle said slowly, remembering their game.

"Well, I don't know if I would say that..."

"Nope, it's too late! You said it out loud!" But his triumph was short-lived. Once again, Beckett was visibly in a quiet torment. For the thousandth time, he wished he could simply grab her and run as fast as he could, hoping for the best. But that was suicide for both him and her. And he could never do that to her.

"Hey, Kate, you hanging in there?" he whispered, tone subdued. Again, his lips brushed against her forehead, as if the single affectionate act could somehow erase her pain.

"It...hurts.." she breathed. "Castle, you should just go, okay? You have a daughter. You have to think of her now." Tears were falling freely down her face and she made no move to blot them.

"No. No, Kate, I'm not going to leave you. I have to think of you too. I've followed you for close to five years now and I'm not going to stop now, not ever. I'm here, okay? No matter how hard you try, you're not going to get rid of me."

Damn his stubbornness! Although it came in handy when solving murders, it was doing Beckett no good now.

"Castle, listen to me. If I move and this thing goes off, you're going to die and it will be my fault. And I can't have that. You need to go, okay? Look, I think we both know they're not going to figure something out any time soon. It's best if you leave. You don't want to die, do you?"

"If I die, if I live, neither one matters if you aren't there, okay? I can't lose you. And if I stay here, you'll keep fighting. Because, Kate, you're a fighter. You fight for the people you love. And now you can fight for yourself...and for me. Because I can't live in a world where you're not there."

Another two hours passed. Beckett was beyond exhausted. Half of her wanted to simply move and end all this, for surely death could not be much worse than this. But she couldn't bring herself to do so. Not when he was there. Not when he was by her side, whispering encouragements, distracting her with something funny, fighting for her when she could barely fight for herself?

The pain continued to wail in her lower body. Some parts of her legs had even gone completely numb. An itch constantly niggled on her foot and it took every ounce of willpower not to scratch.

"Castle..." It had been quiet for the past forty five minutes, both of them not knowing what to say anymore.

"Yeah, Kate?"

"I knew I loved you the moment I saw you." He beamed, but then suddenly fear struck his eyes.

"You're not giving up, are you? I won't let you!" He squeezed her hand as tightly as he could. "You can't give up!"

"I'm not giving up. This is me telling you why I'm not. It's because I love you. And if I were to die, I would be going to a place where you wouldn't be there." Castle's face dawned in understanding.

"Me too." Kate's face wrinkled in confusion.

"If you died, you would go to a place where I wouldn't be?"

"No. I loved you the moment I saw you and I never stopped. And that's why I can't give up on you either."

Just then, Beckett's leg suddenly gave out.

She crumpled to the ground.

Castle went to grab her.

And the bomb went off.

Neither of them could live in a world without the other. But in death, they would never be separated again.