A/N: This is the next story in a mild AU/canon divergence series called The Other Guardian 'verse. There's a detailed note about it on my profile page, but in brief: after Dean is raised from Hell by Castiel, an entire year passes before the Lilith rises and the seals start to break. During that time, Castiel is assigned to watch over the Winchesters, and finds himself growing closer and closer to Sam.

This story is a set of drabbles set over the summer; it follows "Starbright," and focuses on the evolution of Castiel's feelings as he and Sam grow closer, moment by tiny moment. Rotating perspectives, including Dean's; this story is still technically pre-slash, but getting closer to full slash all the time.

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Castiel's hand had been moving on its own. It was a strange sensation. He was not accustomed to thinking of his vessel in terms of its discrete parts, but recently that had begun to change; more and more he looked down to find that his hands were not where he'd left them, that they had moved without his conscious instruction or even his awareness. The mutiny was mildly unsettling; his assignment to the Winchesters was not the first time he had borrowed physical form, but it was the first time that form had ever gotten away from him.

More curious had been Castiel's gradual realization that his hands always moved in the same direction. Toward Sam.

It had happened again, standing in the swirl of disarray that seemed to follow the Winchesters into each new hotel room: loose newspaper clippings and fast-food wrappers and a pile of used towels on the floor of the bathroom which Dean was picking through, searching for the cleanest one to wipe the gun oil from his hands. Castiel was not certain when he had drifted to stand behind Sam, seated at the small table that rocked with the rhythm of his fingers on the keyboard—was less certain when his hand had settled across the chair's top rail, the emblem of a poorly carved rose pressed into his palm and the back of Sam's thick jacket just brushing his curled knuckles every time he moved.

Sam and Dean were engaged in discussion, calling back and forth across the room, but Castiel barely heard them; his attention was fixed on the small patch of skin between Sam's hair and his collar, and how even without touching he could feel the heat of Sam's body against the backs of his fingers. He wasn't sure how such a mild feeling could be so distracting. It was hardly a feeling at all—he was certain a human would not have felt anything, and even as an angel the impression was little more than a prickle at the edge of his senses, the possibility of heat. Somehow that only made him want to lean closer, to reach out and trace the flats of his fingers down the path of Sam's spine, confirm the warmth that tingled on his skin. Castiel found that his hand had unclenched from the back of the chair, and he curled his fingers carefully in once more, watching closely to make sure they moved as they were assigned. The dark wood felt unbearably cold against his fingertips.

"Cas?"

Castiel looked up to find that Sam had turned in his seat, craning his neck back so he could catch the angel's eyes. There was a wrinkle across his forehead that Castiel recognized as confusion; he had the sense that Sam must have asked him something and was waiting for a reply, a theory confirmed by the way Dean was leaning against the bathroom doorframe, his arms crossed impatiently over his chest. Castiel looked between them and then tightened his grip on the back of the chair, scrutinizing Sam's waiting expression once more.

"I apologize. I was…preoccupied. What do you need?"

Sam's eyebrows drew together, one hand straying up to brush his hair out of suddenly concerned eyes. "Cas, you okay? What is it?" he asked, and then, before Castiel had a chance to answer: "If you need to do something else, don't worry about it—we can always get Bobby to overnight us the book instead—"

"Oh, hell no, Sam," Dean broke in, stepping forward until he was close enough to deliver a punch to the angel's shoulder. Castiel glanced down at the point of impact, wondering why he hadn't felt the same heat from Dean. "The mayor of Creeptown here spent the last fifteen minutes staring at the back of your head. He can spare ten seconds for a special delivery. You don't pay for postage when you're being stalked by FedEx incarnate."

Castiel was not certain where Creeptown was; he had almost forgotten, preoccupied with the infinitely small distance between him and Sam, that he had been called down to retrieve something from Bobby Singer's house in the first place. Sam protested for a moment longer and then bent forward to write the title on the hotel's complimentary notepad, and Castiel could not stop himself from leaning forward a few inches too, watching over his shoulder as the pen scratched across the textured paper, the strands of Sam's hair falling softly across his clavicle. Dean retreated to the bathroom, shaking his head. And though Castiel had fought to exert his will over them, he could not stop his fingers from uncurling from the top rail of the chair and reaching out for Sam before he disappeared, three fingertips scarcely brushing the plane of his back—and in the rush of grace after his departure, Castiel pondered the feeling he'd experienced for just a millisecond as he lost corporeal form: the feel of Sam straightening in his chair, the muscles of his back pulled taut under his fingertips, and then the blush of pressure as Sam leaned back ever so slightly into his touch. He wondered if Sam would lean toward him again when he returned.

Castiel was not certain what he understood about Sam, except that there was a great deal that he didn't, and wanted to.