"Thank you," Dean whispered.
Cas turned back; Dean had never felt the need to thank him for his help before. He frowned, confused, while Dean took a step closer.
"I mean it, Cas. Thank you." Dean's eyes were surprisingly gentle, only confusing Cas more. "I want to show you something."
Dean walked to the Impala and opened the door.
"I've seen the backseat of your car before, Dean."
Dean rolled his eyes, making Cas wonder what he was missing. "Yeah, I know. Will you just get in?"
Cas crawled into the back of the car, quickly followed by Dean. "What now?" In such a close space, he could hear the hunter's breathing, quick and slow.
"Castiel, I'm sorry," Dean whispered, barely audible.
"What do you have to be sorry for, Dean?" It occurred to Cas that Dean had used his full name. For as long as he could remember, Dean had called him Cas. What had changed?
Dean leaned in, backing Cas up against the car door. He hesitated, and Cas could see the conflict in his eyes. He took a deep breath and deliberately placed his hand on Cas's thigh. "I made a promise to you, and up till now, I haven't kept it."
Cas's eyes were wide. He wasn't sure what was happening, but it was new and frightening. He could feel Dean's hand, warm and strong, on his thigh, somewhere it had never been before. "I don't understand."
Dean was quite close now. Cas could see each fleck of color in his eyes. Suddenly, his hand was gone from Cas's leg. Dean ducked out of his shirt and moved swiftly so that he was holding himself above the angel.
"Wh- what are you doing?" Cas swallowed loudly, his eyes drawn for some reason towards Dean's bare chest. "Your shirt-" he trailed off as he felt his body react in strange new ways. He inhaled sharply as he felt his penis stiffen.
"I told you, I'm keeping my promise," Dean breathed. "I told you I wouldn't let you die a virgin." He lightly trailed his fingers down Cas's neck to his tie and began loosening it. Cas was frozen with fear and confusion.
Slowly, Dean began unbuttoning the angel's shirt, running his fingers over Cas's chest and making him shiver.
"I… but… you…" Cas stammered, before Dean silenced him by putting a finger to his lips.
Dean moved his hand away from Cas's lips, and framed the angel's face with his hands. "Just…" he trailed off as he leaned in even closer. Cas stopped breathing as Dean softly pressed his lips against his.
"Oh," Cas gasped, and grabbed at Dean's bare back. The pleasure he got from this new scenario was shocking to him, but all he knew was that he wanted more.
Dean ran his tongue across Cas's lower lip, sending a shock through his whole body, while his hands moved down to continue removing the angel's shirt. Cas shivered, desire flooding his body. He frowned, confused by the feelings coursing through his body.
"Just relax," Dean breathed in his ear, moving his lips down to his neck. The hunter moved his hands down and began fumbling with the angel's belt, while Cas began exploring Dean's body on top of him. Cas didn't understand, but he loved the feel of Dean's muscles, hard and strong, under his hands. He could also feel Dean's erection pressing hard against his leg, which only made his grow more.
Dean had finished removing Cas's belt, and began sliding the angel's pants down. Cas realized that his heart was beating frantically; to calm himself he watched his breath play with the messy hair just under his chin.
Cas froze as Dean's head pulled back. He would never tire of looking at Dean's eyes, as green as his were blue. Dean half smiled and looked down. Suddenly, he was holding a small tube. Cas frowned, again unsure of what was happening.
"Turn around," Dean said, his voice rough.
Cas hesitated, "I…"
Rolling his eyes, Dean sighed, and suddenly Cas was being rolled over in the hunter's strong arms. Cas could feel Dean's mouth on his back, his stubble tickled as it brushed gently along his spine.
Cas took deep breaths, trying to calm himself, not sure if he was more scared or aroused. "Just relax," Dean said again, as he slid one finger slowly into Cas's ass. The angel moaned, it was tight, but it felt so good. Dean slid another finger in, then another, this time moving them, widening Cas's hole.
"Oh… oh" Cas moaned again, his body moving automatically in response.
"Mmmm…" Dean slowly removed his fingers and slid his hand around to Cas's front. As the hunter wrapped his fingers around Cas's shaft, the angel clutched at the car seat beneath him. He had never felt anything so pleasurable, and he didn't know if he could handle more.
"This might hurt, just a bit," Dean said, and slid his own penis into Cas's waiting ass. The angel gasped, it was painful, but at the same time, he was in ecstasy. Dean waited just a second, "you good?" he asked.
"Yes, Dean," Cas gasped. He didn't know how, but he knew he wanted more.
"Oh," Dean breathed as he pumped his hips, slowly at first but increasing speed. His hand moved in time along Cas's penis, and the different sensations made Cas squirm. As the rhythm continued, he felt something building inside of him. "Dean…" he said, unsure.
"Yes, Cas, yes!" Dean shouted, and as Cas came, he also felt Dean unload inside of him, adding to his pleasure.
He collapsed onto the seat, physically and emotionally beat, and could feel Dean's hand, stroking his hair. "Thank you."