Castiel swallows, and his tone drops into something lower, something more intimate. Something reserved for their scenes, because this is as much a scene as they can share right now, and he recognizes the subtle command behind Sam's wish.

"Thank you, master. I will."

It's strange to him. He's still getting used to phones and other devices like it, and for a moment, it feels weird to undress when he can only hear Sam, not see him.

But then, he'd never deny the request. So he takes a deep breath, puts the phone on speaker and places it on Sam's pillow while he gets undressed. His clothes rustle, and he keeps his voice low as he tells Sam what he's taking off and when. There's a strange intimacy to it.