Dean fought down the flutter of nausea as he watched Castiel slash the silver blade across his forearm. "Cas, why do all your plans involve opening a vein?"
"Blood magic is old, Dean. It's powerful." He picked up the shallow clay basin he'd brought with him and held it under the wound to collect the dripping blood. "Anything less is base slight of hand by comparison."
He frowned for a moment as he watched the blood pool, then picked up the knife and slashed his arm again, deeper this time; Dean had to turn away as the blood flowed out in a steady stream. "Dude."
"You asked me to help you pass unseen through a demonic sacrifice. This is what that requires." His lips twitched up into what Dean thought was way too close to a smirk. "Feel free to leave the room if you're too squeamish."
Dean glared at him. Even if he'd wanted to duck out, he sure as hell couldn't now with Castiel saying that. He sat back on the bed and tried not to fidget; he'd already agreed to let Cas fingerpaint on him in blood to get this done and the longer he took getting on with it the weirder the whole thing got. Frankly, if he'd known if it would have taken this long he wouldn't have taken off his shirt already. The motel felt like a refrigerator. "Quit being a smart ass and let's go."
"Hush." Dean could swear Castiel was enjoying this. "I need to concentrate." He held the bowl out in front of him in both hands and closed his eyes. He let out a measured breath, exhaling into the bowl for so long Dean wondered how much air his lungs could hold. He saw steam start to rise from the bowl; when he inched forward he saw that the blood was actually boiling.
When Castiel began to chant Dean felt the hair rise on the back of his neck. The monosyllabic words hung in the air, heavy and somehow almost alive. They thrummed under his skin; Dean felt his heart start to beat in time to the words, like it wasn't even part of his body. He watched Castiel's lips move with each new word, forming them as carefully as if he were sculpting with sound. The air grew thicker with each passing second; the motel room lights flickered on and off, the TV flipping to random channels until it finally sparked and went black.
Then Castiel stopped speaking and everything went back normal; he staggered back a step and and Dean reached out a hand to steady him. "Dude, you okay?"
Cas waved him off. "Fine. I'm fine." He had circles under his eyes Dean was certain hadn't been there before. "We should start. The ritual will require time afterward to set." He took off his trenchcoat and rolled up his sleeves, dipping his fingers into the bowl. "Try to hold still."
The blood was still hot when it touched Dean's skin. "Cas. Jesus."
"I apologize," Castiel said. "There isn't time to let it cool."
Dean closed his eyes as Castiel traced the first sigil into his skin, just over his heart. The site tingled for a second, almost like a mild sunburn, then Dean looked down just in time to see the sigil flicker and disappear. "Okay, that's a little awesome."
Castiel was clearly pleased with himself. "You might want to get comfortable. This will take some time." He painted the next sigil on Dean's left shoulder, very close to his handprint scar, then slowly made his way across Dean's chest. From the right shoulder he started moving down on a diagonal, stopping just below Dean's navel. Dean couldn't help squirming as Cas' fingers skated over his ribs. "I need you to hold still."
"I can't help it, man, I'm ticklish there." Castiel's eyes darted up at him; Dean jumped when he touched him again, and from the way Castiel's lips curled up Dean knew he'd done that on purpose. "Not fair, Cas."
Castiel didn't answer, instead working his way back up Dean's body until he'd formed an upside down triangle. Just as he finished painting the last sigil to form that side Dean saw his eyelids flutter. "Whoa. Cas," Dean said, catching him as he started to sway forward. "Not the time to take a nap." Castiel's eyes blinked back open, like he was startled. "And don't say you're fine again."
Castiel shook his head. "The ritual is taxing," he murmured. He braced himself against Dean's shoulder, leaving a bloody handprint.
"Hey," Dean said, honestly a little worried now. "You trying to make my shoulders match now?" That almost dragged a smile out of Castiel, although the tension lining his forehead didn't decrease. He did move his hand away, uncharacteristic embarrassment flashing across his face. "Take a breather if you need it."
"I can continue." He did take a moment to collect himself, his hands shaking so hard Dean reached up to steady them, which of course got his hands all bloody too. "Dude. Take a break."
Cas just shook his head again. "The ritual needs to be completed within a certain time frame." He let out a long breath, squeezing Dean's hands.
Without really thinking about it Dean kissed his fingers; the sensation of blood on his lips was strange but God, did Cas look like he'd needed that. When Dean flicked his tongue over his lips he felt Castiel tense, his eyes suddenly intense and bright. The enchanted blood tingled against his tongue. "You like that, Cas?"
Castiel flushed, a fine tremor running through him. His breath caught as Dean kissed his fingertips; the coppery tang of the blood was stronger this time but hey, it wasn't as if Dean had never tasted blood before. And even if the taste had been a problem, the look in Castiel's eyes would have erased it; he looked like it was taking all of his self control to not just throw Dean down to the bed then and there. So of course Dean pushed his luck, sucking on Cas' fingertip; Castiel let out a sudden, helpless little whimper and Dean had never gotten so hard so fast. "All angels such kinky bastards or are you just special, Cas?" Dean whispered, his voice rougher than he'd expected.
Castiel didn't answer. He drew his thumb against Dean's lower lip, shaking when Dean licked it away. He dipped his fingers back into the bowl and went back to painting sigils on Dean's torso, more slowly this time, his intense eyes locked on Dean's face to catch his smallest reactions. The air was almost too thick to breathe, the way it had been when Castiel had been chanting. Dean watched his tapered fingers caressing his skin and thought about what else he'd like Cas to do with those fingers. He groaned as Cas painted a complicated sigil just above Dean's waistband, taking an excruciatingly long time to finish. "Cas, man, Jesus," he muttered, unable to hold still.
"I'm nearly finished, Dean," Cas answered, the rasp in his voice so deep it almost swallowed the words. Dean kissed his forehead and Castiel shivered, his hands trembling against Dean's skin. He painted one last sigil, again over Dean's heart, and Dean felt heat suddenly spread through his entire body. Dean leaned forward and kissed him, sliding his tongue past Cas' parted lips and relishing the surprised breath that drew from Castiel. Cas kissed the bloody handprint he'd left on Dean's shoulder; and Dean had never heard Cas moan the way he did when Dean licked away the blood that clung to his lips. "You said the spell had to set, Cas," he said, already starting unbutton Castiel's shirt. "How long we got?"
"Twelve hours," Castiel whispered back, and Dean could barely choke back his own moan as Cas licked along the line of his collarbone.
Dean kissed his fingertips, sucking on each in turn until Castiel was breathing so hard he was practically gasping for air. "I think we can figure out a way to pass the time, huh, Cas?" Dean said into his ear.
Castiel's only answer was to push him down to the bed, already beyond words. Dean gave up on the rest of the buttons and just tore the shirt open, running his hands down Cas' ribs as he sucked at the hollow of his throat. He kissed the bloody palm of Cas' hand and felt him shudder, burying his face against Dean's shoulder and moaning into his skin.
Dean slid one hand past Castiel's waistband and felt Cas press against him, already needy and whimpering.
Twelve hours wasn't going to be nearly long enough.