Dean bites at his lip while he watches Cas undress, slipping his trench coat and jacket off, draping them over the back of the seat. He’s already out of his jacket, the only thing between them now two layers of thin shirts and denim and years worth of nervous energy ready to burst.
Cas doesn’t move for a moment, just taking in Dean, sprawled and breathing hard beneath him on the seat of the Impala. Normally, Dean would be annoyed coming to a stop when everything’s finally starting to move, but with Cas, he understands. He stares back, just as amazed, until Cas finally drops his hand to his waist and slides it up his shirt.
Dean’s head presses back into the car door as Cas’ fingers trail over his skin, pinching lightly in just the right spots, making him hiss. Dean hears the clink of his belt, Cas trying to undo it one-handed, and immediately reaches between them to help. The layers are quickly disappearing, nothing but Cas’ clothes left when he slips Dean’s jeans and boxers down out of the way and wraps a hand around his cock. It feels good—fuck, it feels good—but Dean grabs Cas by the wrist and makes him stop, breath hitching and his stomach feeling like it’s floating.
“Wait, Cas, just. Wait.”
His eyes are still slammed shut, but he can feel Cas looking at his face curiously. He takes a few deep breaths, waiting for the shaking sensation in his belly to go away, but it just gets stronger, especially when Cas’ thumb strokes against his skin absently.
“Look, this—with us and everything—if you don’t want. I mean, I won’t be—”
“Dean, are you trying to give me an out?” Cas interrupts, sounding amused. Dean peeks an eye open then and gives Cas a half-glare, because yes he is, and he doesn’t need to be made fun of. Cas’ hand tightens and moves around Dean’s cock, making him gasp and his entire body arch off the seat, eyes closing again.
“I won’t let you go. If we do this, I won’t,” Dean warns, his arm reaching up to wrap around Cas’ shoulder, fingers digging into his shirt at the back of his neck. Cas ducks his head forward, pressing a smile against Dean’s lips, and strokes again, making Dean moan.
“I’ve been waiting a long time to hear you say that,” Cas laughs quietly against his mouth, working cool hands over Dean’s hot skin in steady, loving strokes.