"Look, fair's fair," Dean tells Cas for what feels like the two hundredth time. "This thing we got going? Is good. Is awesome, even. Well, after that awkward business where you kept--"
"I don't think I like conversation very much," Castiel says, but he hasn't fluttered off. That's a good thing, because he's still half naked, shirt partway down his shoulders and lips kiss-swollen, and Dean's not sure the world's ready for Wet Dream Cas with Bonus Angel Action hitting the streets just yet.
Dean sighs and settles back down on Cas' lap, ignoring the plaintive, unhappy curve of Cas' mouth. "Fine, let's get to the chase. Sometimes what a guy wants is a good ass-fucking, as in, a fucking in the ass. And sometimes I? Am that guy exactly." He paused, waiting for Cas' reaction. "Who'd like to get fucked in the ass, in case you missed that part."
"I heard you the first time." Cas sounds a little less irritated than the last time Dean brought the topic up, which he counts as a win. "I'm just not comfortable--"
"You're an angel!" Dean groans. "How in the hell is fucking you in the ass any more 'comfortable' than you fucking me? Don't get me wrong, I love your ass, but I swear, it's good for everyone if we change things up a little."
Cas' fingers clutch weakly at Dean's hips, resolve fading. "Dean, you don't understand."
"Oh, come on." Dean rises off him, frustrated, but only goes far enough to kick off his boxers and then drop back on the mattress, supine and ready. With his arms and legs splayed wide, Cas' eyes go predictably dark, and Dean grins. "You know you want this."
"This is inadvisable," Cas says, but he's already touching Dean's feet, his ankles, his calves. "There are things about me you don't know."
"And there are things about me you don't know," Dean replies, humming appreciatively when Cas' hands slide under his thighs, fingers skittering curiously up where it's even warmer. "You don't know how I feel like inside. I haven't had it in ages, I bet I'm really tight. Tight and hot, and I bet you can make me scream. You like making me scream, don't you, Cas?"
"Please don't..." Cas' cheeks are flushed, and Dean thinks smugly that he's still got it.
"Check this out." And Dean hooks his hands under his knees, lifting them up proud and limber, ass on display. Cas looks like he's having a heart attack, but it must be a fun one, because his dick is rising up and all the way interested. Dean shimmies a little and says, "Your cock, in there, capisce?"
"I'll hurt you," Cas blurts out. "This penis doesn't work the way yours does, it'll--"
"For fuck's sake--"
Dean goes still. Cas is bent over him but he is still like a statute, implaccable and unmoving, a dark order in his gaze for Dean to stop and shut up. Dean swallows, though he feels a little guilty for finding that really fucking hot.
"If I put my penis in you," Castiel warns softly, "It will swell at the base, and lock inside you. Your body, tied to mine, for a few hours at least, until I am sated. There will be no escape for you, no reprieve."
Dean stares up at Cas, mesmerized. "Promise?"
Cas blinks. "This isn't a joke."
"I hope to hell not," Dean says, grabbing Cas and pulling him down for a startled kiss. "You serious? Marathon sex? Like, for real freaky angel marathon sex? Your brain's for shit, Cas, why didn't you say that before?"
"Dean, this isn't--"
"Come on, come on, come on," Dean mutters, grabbing Cas' cock and trying to aim it for his hole. His whole body is tingling, because it isn't often Dean gets to try something new, and fucking yeah was this completely new, Cas' prize dick with its secret bonuses, and he's going to get to ride it for hours, holy hell, was he going to be fantastically sore later.
Cas looks hilariously put out when Dean impales himself on his cock, legs wound tight around Cas' waist in an attempt to get him as deep as possible.
"Oh, yeah," Dean groans, the initial fullness at being filled up a temporary relief. He grabs Cas' ass, trying pull him closer, and curses at the first brush against his prostate -- the first of many, no doubt.
And then Cas starts swelling, and Dean's garbled laughter turns into moans.