Another two hours of road-time and a quick stop at a local diner for some dinner (and pie) saw them safely home. They left most of their stuff in the car, grabbing their backpacks and heading straight for the library. Sam was tired from the drive but Dean was determined to fit in some research before bed. Not wanting to leave his brother alone to fret all night, Sam stifled another yawn and joined him. He collected all of the books they had on witchcraft and sigil magic and stacked them on the end of the table. Dean grabbed the seat directly across from him and flicked on one of the little amber lights before selecting a tome of the top of the pile. After an hour of little progress Dean broke the silence. "You think Cass might know something?"

Sam was rubbing his tired eyes with a thumb and forefinger. "I dunno," he offered noncommittally. "Maybe? It's not like it's his specialty but he has been doing some hunting of his own recently. He might have encountered something." That seemed to be good enough for Dean, who snatched up his phone and stepped into the other room to make a call. Sam sighed again, turning back to his own research. Sigils are more effective and reliable when directed toward a positive will, like safety, health, fertility, or love. Sam honed in on this sentence, which had until now been floating in a choppy sea of irrelevance. He quickly turned the page to the next paragraph. Harnessing sigils with an evil will renders most sigils weak and unreliable. These negative sigils have been known to inflict minor damage on all that come in contact with it, including on occasion its creator. Sam huffed in hopeful relief. While this didn't confirm that the mark on his neck was indeed a sigil, if it was it meant that it likely wasn't lethal.

Dean entered right on cue. "Find anything?"

"Sort of, yeah. Here." He pointed to the passage he had just read. Dean leaned over the text, hand resting loosely on the back of Sam's chair. Sam watched closely as Dean's taut expression softened with each word he read. By the time he reached the spot where Sam had left off, his face had shifted from one of worry to one of skeptical hope.

"It's a start," he huffed, not willing to relax completely. He clapped Sam on the shoulder before resuming his seat.

Sam smiled and let out a soft breath, glad that his brother had relaxed at least a little bit. The aura of tension that had been radiating off of Dean for the last few hours had finally subsided to normal Dean-is-worried levels. He caught himself rubbing his hand over the bandage on his neck again; the skin underneath had been prickling hotly for the last half hour. Not wanting to alarm Dean any further, he tried to ignore it. He glanced at Dean, who had his head buried in a book almost identical to his. Maybe if he excused himself to bed, he could take a look at it without arousing Dean's suspicions too much. Maybe he could get Dean to go to bed as well? Heavy bags still nestled under his brother's eyes, darker than usual thanks to his enforced sleep deprivation the night before. Sam felt his lips pursing with concern. Dean had been letting himself run on empty far too much lately. If he kept it up it might just kill him. But Sam would die before he let that happen. He stood and let out an obvious yawn.

"Night, Dean." Sam said as he started off toward the bedrooms. He expected to hear a grumbled response or the loud thud of his brother shutting his book. Instead he felt Dean's warm grip land firmly on his shoulder; Dean had stood so quietly Sam hadn't even heard him. His heart couldn't decide between leaping into his throat or slipping into his stomach, so it did both.

"Lemme take a look at that before you go," Dean offered quietly. Sam could tell from his tone that Dean had read him like an open book. He had assumed that Dean was so distracted with research that he wouldn't have noticed Sam messing with the bandage. He didn't know that Dean had become attuned to his every movement, watching judiciously for some sign of trouble. He wasn't about to let his brother hide any symptoms from him, and knew that Sam would do exactly that given the chance. So every stretch, every yawn, and especially every motion related to Sam's neck registered clearly in his periphery.

Dean didn't wait for Sam's response, pulling the bandage off with gentle fingers. Sam marveled at Dean's mild touch, soft even with hands that were thoroughly trained in stabbing, shooting, and strangling monsters. That was why Dean was always in charge of first aid; Sam could get it done, but his work often left scars. Dean could wield a needle with such finesse that Sam had half the scars his brother did.

Dean inhaled slightly and frowned when the scars came into view. The cuts had completely healed, much too quickly to be natural. In their place stood deep purple lines; more marks had spread from the initial mark and created a complicated overlay of curving intersections and circles. In its current state it still looked incomplete, like there was still the potential for more to grow.

"Why'd she gotta be so thorough," he grumbled as he snapped a picture and handed his phone to Sam. Sam huffed in annoyance; this added who knows how much time to their research. Sigils they knew. Sigils that progressed after the caster had already died? Not so much.

"Any word from Cass?"

Dean shook his head. "Not yet. Left a message." He was watching Sam's face closely, a silent question rumbling behind his solid gaze. "How does it feel?" He said, his tone relaying his actual meaning: Were you trying to hide this from me?

Sam shrugged. "It was itching, but all cuts itch. I just thought it was healing." His tone was light, non-committal.

Dean wanted to smack him upside the head. "That counts as anything, Sam." Don't hide it from me. Sam let out a laugh and threw Dean a look that suggested he thought his brother was seriously overthinking things. Dean just sighed. "Does it still itch?"

"A little."

"Hm." Dean grabbed Sam's shoulder again, from the front this time, and pushed him down into a chair. Sam landed with a heavy thump, not willing to fight his brother after accidentally almost hiding something pretty important from him. "Will it hurt if I touch it?" Sam shook his head. Dean kept his grip on Sam's other shoulder as he ran the fingers of his right hand over the marks, searching for any scarring. He worked diligently, checking each line with soft fingertips. One line seemed to extend farther from the original mark than the others, heading straight up the neck toward Sam's ear. He followed it slowly, wondering why it also seemed to be lighter than the rest of the scars. Sam shifted suddenly, reaching up and pulling Dean's fingers off his neck. "Sam?" Dean asked, tone tinted with concern.

"That tickles. Stop it." He gave Dean a small smile. Dean lowered his hand and stepped away without complaint, keeping a very close eye on his brother as he regained his feet. Nothing seemed amiss; Sam's face just seemed a bit flushed. After considering their proximity a moment ago, Dean colored slightly himself. Sam excused himself and made for the showers, hauling his backpack over his shoulder as he went. He rested a hand loosely on the left side of his neck.