Yeah angel Cas doesn’t need to physically sleep but he loves to lay with Sam as he sleeps.
Sometimes Sam is the big spoon wrapping Castiel in his ridiculously long limbs. Sometimes Sam, despite his size, is the little spoon. He loves to feel the warmth and safety of his angel holding him. Cas doesn’t sleep but he lays with Sam every night and admires Sam’s sleeping form. His features so much softer and relaxed in sleep. At first it was slightly odd for the angel, just lying in bed for hours as Sam dozed. But it quickly became a beloved part of their routine. Cas loves the feeling of Sam’s slow heartbeat all through the night. They’re both at peace knowing that the angel is there to keep Sam safe if need be. Sam sleeps so much more peacefully now that Castiel is there by him. Sometimes Sam has nightmares but Castiel always soothes them away the moment he senses them.
Being in Sam’s bed, holding the large man in his arms, listening to his steady breaths and feeling his strong heartbeat, knowing that while he’s with Sam that he will let no harm come to the hunter, there is no place on earth nor in heaven that Castiel would rather be.