It started on a Monday.

Beckett had just finished a case Saturday, a case that was less difficult to solve than usual, but more dangerous. Over the course of the week she had been pushed, hit, kicked, tackled, and shot at more times than she cared to count. Every time Castle had been by her side in seconds, his face contorted by fear and shock.

Monday morning she called with the news of a dead body. After waiting longer than usual to answer, he waved her off, saying he had writing to do.

She tried again Tuesday. This time he said he had a meeting with his lawyer about a contract, but she had a feeling he was dropping a hint. Wednesday she didn't call.

Wednesday night, Castle brought her Chinese from her favorite take-out restaurant, so he couldn't have been avoiding her. She began to regale him with the particulars of her case. His eyes sparkled with curiosity, and he even offered some dramatic theories, but when she asked if he wanted to come along, he just refused casually. He headed home while she headed out with Esposito.

Driving home that night, Beckett tried to think about the case, but the question burning behind her eyes was about that damn writer. Before she could stop herself, she found her car steering towards the Castle loft. He answered the door by her third angry knock and she stormed past him into the hall.

"What's going on, Castle?"

"Uh…Beckett? What are you doing here?"

He probably would have appreciated a minute to get his thoughts straight, but she knew she'd get more honest answers if she pressed.

"Don't ask me that Castle. Why haven't you been investigating with me?"

He shrugged as he stumbled for words.

"I just…"

"You just what?"

"I've been busy."

"Is that all?"

He was starting to sweat a little, even as he began to wonder if it was legal for her to use her interrogation skills apart from a criminal investigation.

"Yes."

"Fine," she answered, her face entirely too stoic for him. "I'll see you tomorrow." She turned to walk out.

"Well—"

"Well, what?" she demanded as she spun back to face him.

"I'm…"

"You're what, Castle?"

"I'm done!" he exclaimed finally.

"Done? Shadowing me?"

"Yes."

"But…you still brought me dinner," she commented, trying to connect the dots.

"I…I don't want to stop seeing you entirely," he confessed. "I just…"

"Just what?"

He sighed.

"I can't."

She gave him an odd look, clearly not getting it.

"You can't what, Castle?" she prodded, more confused than angry now.

"I can't watch what you do any more."

"Ah," she chuckled coldly. "Too dangerous for you, huh, Castle?"

His face hardened. "No," he said. "For you."

"What?" she asked, shaking her head as her face contorted to show her befuddlement. "What are you talking about Castle?"

"Every day," he started in a loud grumble. "I watch you pick up clues and question witnesses and empathize with survivors. I watch you put the pieces together like a puzzle and joke with the guys and even share girl-talk with Lanie. And it's beautiful and…amazing." He paused, making sure he had her eyes before taking the risk of continuing. "You're beautiful and amazing."

She felt the blood rise to her face. As she tucked some hair behind her ear, her palm brushed her cheek. Her skin was warm.

"And every day, you're risking your life."

She laughed, wondering if this was some strange joke. "It's my job!" she insisted.

"I know," he agreed softly. "And you're good at it. I can live with it without going too crazy because I know you're good at it. But I can't watch it anymore."

Castle," she said slowly. "You aren't making…any sense."

"I can't watch your brushes with death anymore, Kate. I can't do it. I'll exchange theories with you at the precinct, feed you, and you are, of course, welcome here whenever you like. But I can't watch you almost die again."

She nodded, infuriated now.

"Okay, she said, getting more worked up by the second. "Okay. But, just so you know, Castle…just because you aren't going to see it doesn't mean it isn't going to happen. And when it does, it would be nice if I had my partner there to watch my back."

He hung his head, sighing from emotional exhaustion. He was bent over, his arms straight, his hands spread apart and resting on the counter as she slammed the door on her way out.

Her words had caused him two nights of lost sleep when he got the call.

"Castle…"

The hesitation in Esposito's voice felt like a hand seizing his heart. When he finished with "It's Kate," the hand squeezed.

Castle was at the precinct as quickly as he could be. He thought he drove, but if so, he had no idea what happened to his keys. Everything from the moment he heard her name to now was a blur. Did he turn the stove off? Did he lock the door?"

And none of it mattered because, damn it, a bullet had finally hit her, and why had Esposito told him to be at the precinct instead of the hospital? Where was someone who knew what the hell was going on?

"Ryan?" Castle did a double take. "Ryan!" he exclaimed, running towards him. "Where's Kate?" Castle was out of breath and so distracted that he barely registered as Esposito walked up to him and placed a hand on his shoulder.

"I'm sorry, bro. I know I promised you I'd keep her safe, but—"

"No," Castle interrupted, frozen. "I should have been there." Louder he went on, "Damn it, me and my stupid—"

He cut himself off as a very animated gesture of frustration got him turned around and staring straight at –

"Kate?"

"Beckett," she answered.

"You…you're fine!" he exclaimed in shock, almost angrily.

With a bemused look, Kate approached him. He noticed the arm sling for only a moment before retuning his gaze to her face.

"Yeah…" she replied hesitantly. "Should I not be?"

"Espo—" Castle sputtered. "Esposito said you were shot!"

She shrugged. "Just a graze."

Castle's mouth was agape and Kate was far too calm. He turned to see Ryan and Esposito chuckling. Castle held his arm out before him, clenching and reopening his fist as his mouth moved to form unutterable sounds. Finally, he clenched his fist one last time as he lowered his arms, shifted his gaze upward, and sighed. Looking back at Kate, he made the decision that from now on, he would act like her partner should. When she went out to put her life on the line, he would be right next to her, because he was her partner. Sure, she was tough enough to take care of herself, but it was his job to watch her back, and from now on, he would.

With a decisive nod, he turned towards the elevator. Waving to her, he called, "See you in the morning."