This is basically a pointless oneshot crossover with established Dean/Harry, featuring an appearance from Cas.

I don't own anything.

"Ow!"

"Just…move that way."

"I hate you."

"You usually do this kinda thing with people you hate?"

"The steering wheel is digging into my back!"

"Stop whining. Just…here, get closer."

"I'm not whining. This is just-"

"Passenger seat then?"

After several minutes of maneuvering, and a few bruises, a very naked Harry was sitting in the lap of a fully clothed Dean in the passenger seat of the Impala.

"Better?" Dean asked.

"Yeah, sure." Harry glared down at Dean. "Why are you fully clothed again?"

"I told you, I wanted it this way."

"Right. And we just have to do everything you want." Harry grumbled the words but didn't protest further when Dean pushed him towards the dash just enough so he could unzip his jeans.

"Well, we can't go back to the motel," Dean reminded him, sharply.

Harry winced, reminded of why he'd agreed to this. "Fine, sorry." Not-Sam was back at the motel, with his creepy emotionless gaze and his creepily flat voice.

Dean pulled himself through the hole in his boxers and Harry reached for his wand, casting a few quick spells on himself and Dean, leaving him with that strange empty, wet feeling. He didn't use the spells a lot, finding that he liked the regular preparation almost as much as the actual act but they were on a bit of a time table.

Dean gripped his hips almost hard enough to bruise and bit his lip as he surveyed Harry before lifting him, only to lower him down slowly. Harry reached down, between them to grip Dean in order to guide it better and Dean sank into him.

For a second, Harry didn't move, adjusting a bit, feeling the bite of Dean's zipper on his ass before Dean lifting him again, and then brought him back down. Dean set a steady pace, bringing Harry up and down on him.

Harry was about to reach his peak, could feel his orgasm building when a voice that was definitely not Dean's broke his concentration. Harry froze on a down stroke, Dean's hands stilled and he sat there, Dean still buried deep inside of him.

"We need to speak about something urgent."

Harry glared, horrified, at the angel that had appeared in the backseat of the Impala. Cas seemed utterly unaffected by the scene.

"Cas," Dean started, sounding more frustrated than anything else. "What did I say about the interruptions?"

"To not interrupt while you were in bed. You are not in bed."

Harry gaped at him and, not for the first time, wondered if Cas was really this clueless or if he just acted that way to annoy the people around him. When he remembered the two times Cas had, in fact, interrupted them in bed, he was sure the angel knew just what he was doing.

"You know, considering all the times I've caught you watching me sleep, I guess it's not that much of a surprise that you're into watching," Dean commented, idly.

"Why are you still here?!" Harry asked loudly. His surprise at Cas' appearance had gone, leaving behind anger and embarrassment. Of course, Dean wasn't embarrassed. Dean was fully clothed except for the part of him buried in Harry's ass and Harry wondered a moment if Dean had asked for that because he thought something like this might happen.

"I have told you, I need to speak with you-"

"I don't care!" Harry interrupted him. "Get out now before I find a spell that'll hurt an angel!"

"Harry, I do not think-"

"Get out!" He only settled after Cas finally disappeared, but he still glared at Dean. "I hate your friends."

Dean laughed at him and Harry forgot to get angry when Dean pulled him firmly down, rotating his hips at the same time, hitting that spot. When he got his breath back, he made a promise even as he let Dean pick back up the rhythm he'd had before Cas' appearance.

"I'm going to get you back for that. You and your little angel."

Dean only laughed again, then brought them both over the edge.