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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There was something rapturous about man in his sleep.

Castiel stood at the edge of the bed, looking down at the gentle splay of Sam's sleeping form, his limbs utterly quiet beneath the white sheet, his hair a soft whirl about his face. Castiel had long observed the instincts in man that were war, greed, faithlessness, bloodshed—but this was an aspect of humanity that he was only beginning to see, the beauty of the absolute stillness, the faith that was inherent in closing their eyes and trusting the world to leave them untouched until they awoke. The angel considered Sam's face turned into the pillows, the way the muted light through slatted blinds softened every line of his features, turning his nose, the slope of his jaw into gentle rises and falls, as mild as his shallow breaths. In sleep man was as a child, innocent, unknowing, washed clean of all transgressions. In sleep, man was captivating.

A loud snore pulled Castiel's eyes to the other bed, where Dean lay sprawled in a heap, one leg jutting off the back of the mattress and his open mouth ringed with glittering drool. Castiel's eyebrows drew together as he turned his gaze decidedly back to Sam.

It was not his intention to wake the Winchesters; what he had to say could wait for a later time. But he could not quite stop himself, before he departed, from reaching out to smooth a strand of Sam's dark hair down against the threads of the pillow—nor from entertaining the possibility, as he lifted his wings, that it was not man in the infinite that was captivating. Perhaps it was just Sam.

.x.

"I apologize, Sam."

Sam looked up from his laptop at the angel who had reappeared in the middle of the hotel room, looking, as usual, slightly ruffled. Sam stood up from his chair at the small round table.

"Hey, Cas. Where's Dean?"

The angel cast a fleeting glance at the door before his eyes came back to Sam. "He will return shortly. I came ahead to apologize to you. Dean has made it clear that I assaulted you earlier. It was not my intention."

Sam winced a little at the memory of Cas arriving in the hotel room fifteen minutes before while Sam stood at the microwave reheating his gas station coffee, and how Castiel had, with a very awkward attempt at being casual, reached out and planted his hand right on Sam's ass. It was so obviously a mistake that Sam had tried to brush the whole incident off, but Dean, on his way out of the bathroom with toothpaste foam caked around his mouth, had basically blown his top. Sam had heard him shouting all the way down the hall outside the hotel room as he dragged Cas off for a "little chat."

Castiel seemed to be waiting for a response, so Sam dredged up a smile that wasn't too uncomfortable, a shrug rolling through his shoulders. "It was an accident, Cas. Don't worry about it, okay?"

"Dean has explained the restricted zones to me," Castiel replied, glancing at the crotch of Sam's jeans in a way that made it clear Sam's older brother hadn't done a good enough job explaining everything. The angel's eyes lifted to meet Sam's again. "He has also suggested I refrain from touching you in the future, to avoid mistakes."

"Oh, Cas, you don't…"

Sam bit his lip. Dean would be pissed that Sam was undermining him in the angel education department, especially so soon after delivering his ultimatum—but remembering all the times Cas had tried to reach out to him in the last week or two, so obviously trying to make a gesture that was as unnatural to him as Sam breathing underwater, Sam couldn't bring himself to slap that hand away. And even though he knew he shouldn't be pushing his luck, he also knew he couldn't live never feeling that gentle hand on his again, even if that would never mean as much to Castiel as it did to Sam. He gave Castiel a full smile and took the last few steps to close the distance between them.

"Touch isn't necessarily a bad thing, Cas," he said. "It's just certain places, you know? But, like, when you touched me on the shoulder the other day—that was fine." Castiel's expression was as blank as ever, but somehow Sam had a feeling he wasn't getting through; without letting himself think too hard about it Sam reached out and grabbed Castiel's right hand with his, bringing it up to rest above his collarbone. "The shoulder. Right? Or, the arm's fine…" He slid Castiel's hand down to rest on his bicep. "The back's okay, too, just a little higher than you… like, here," he said, dragging Castiel's hand behind him and settling it against the dip in his lower back. He gave the angel an encouraging smile. "Got it?"

Castiel looked up at him and wound his fingers into Sam's loose shirt. "I do. Thank you, Sam."

"No problem," Sam returned, and his chest felt light like his heart had evaporated right out of it as Castiel's eyes crinkled into a not-quite-smile. Then the door swung open and Dean screeched to a halt in the doorway, half-gaping, half-glaring at his younger brother through a mouthful of toothpaste.

"The hell, Sam?" Dean demanded.

Sam had a feeling he was going to hear about this all day in the car.

.x.

"I guess tan's your favorite color, huh, Cas?"

Castiel straightened from where he had been studying a rack of oversize sweatshirts, all of them emblazoned with a red slogan in block letters declaring I'm Kind of a Big Deal in Nebraska. Sam stood behind him in the narrow gas station aisle with a pair of plastic sunglasses dangling from one hand, the other clutching a spotted banana and the bag of Flamin' Hot Cheetos Dean had asked them to buy on his behalf while he put gas in the car. Castiel released the sleeve of the pale brown sweatshirt he had been scrutinizing and turned to face his companion, his eyes narrowed uncertainly.

"Why would I have a preference for one color in particular?" he asked.

Sam raised his eyebrows, his lips twitching into the little smile Castiel knew by now meant he had asked about something humans considered utterly basic, perhaps even automatic. Sam shook his head and the sunglasses mimicked him, swinging like a pendulum from his index finger. "Well, I was joking, Cas—because of, you know, your coat and then…" He gestured to the sweatshirt Castiel had been examining, but then seemed to change his mind, waving the bag of Cheetos as if to dispel his unfinished thought. "Never mind. It's just a human thing, I guess; most people sort of prefer one color. I thought maybe angels did too."

Castiel glanced back at the rack of sweatshirts, recognizing for the first time that they were dyed in an array of different colors and wondering what it was in man's nature that was so inherently divisive, driven to define itself through an infinite register of particularities. Then he looked up at Sam, worrying the bridge of the sunglasses with his little finger, and decided that perhaps that was wrong—perhaps it was just one more manifestation of the singularity of a human soul, and the uniqueness that made them breathtaking. Castiel took a step toward Sam and the young man pulled his hands in, making space for them to stand toe to toe in the narrow aisle.

"What is your favorite color, Sam?" he asked, certain suddenly that this was something he very much wanted to know.

Sam gave a short laugh, as if the question surprised him. "Honestly, I haven't thought about it in a while. When I was little, it was green, but lately I guess…I guess I like blue," he finished, his teeth digging softly into his bottom lip as his eyes found Castiel's again. "Not really bright blue like the sky, but just…I don't know. Some of the most beautiful things I've ever seen are blue."

As he finished, his voice dropped nearly to a whisper, and for a long moment the fading syllables hung between them as Castiel studied him silently, trying to decipher the strange expression on Sam's face, neither awe nor longing but something in between. He leaned forward to get a closer look. Then Sam took a sharp breath and moved his right foot backward half a step, carving out a space between them once more.

"Like…the ocean," Sam added, his elbow rattling a rack of yellow bags labeled Funyuns. "Or, um, Neptune, or something. I'm gonna check out before Dean comes in and gives me the third degree—he gets pissy about his junk food. Did you want anything, Cas?"

Castiel shook his head, and then held his ground for a long moment, watching Sam retreat toward the register with the sunglasses pressed to his chest, as if holding something in. Overhead the intercom sought out shower customer thirty-nine. Castiel wondered if any human language was capable of explaining to Sam what Neptune looked like to angels, and why Sam had spoken of the ocean as blue, when it was anything but—a dazzling cacophony of brown and green and a ripple that was only light, racing up the sand on the transparent surf. A much more complicated color than blue. Titian. Auburn. The color of Sam's eyes sometimes, when he looked at Castiel.

Perhaps that was his favorite color.