Human. This is beyond strange. He had to travel by machine! The body he usually wore like a coat had become so demanding – it wanted to eat, it wanted to drink, it wanted to sit down, it wanted to pace, it wanted to… do certain things that Castiel was absolutely sure he didn't want to get into. Well, his mind was sure; his body, with its newfound independence, had other ideas.

Was this what it was really like for Dean and Sam all the time? No wonder they were both so often angry and impulsive. They just couldn't help themselves. Hm. It seemed he would have to obey his body's demands to an extent, but he would have to retain as much control as possible if there was still to be one reasonable person between the three of them.

This resolution seemed to have been successful until the second night at Bobby's. He lay down to sleep – another new thing – expecting the complete oblivion he had experienced each human night previously. But this time, once he had fallen away from consciousness, he found himself surrounded. Angels and demons, monsters he had thought were destroyed; and though he did everything he knew, it was useless. His sword shattered in his hands before he could thrust, all the spells he shouted came out wrong, and their numbers just kept increasing. He saw Dean and Sam there, but when he looked closer he realised that they were just vessels now – but Lucifer was in Dean and Michael was in Sam. It was all wrong.

"Hey Cas!" Sam/Michael called. "We've had a talk –"

" – and we've decided to settle our differences," Dean/Lucifer finished, linking arms with his brother.

"That's – incredible," Castiel replied, bewildered.

"Mm," Sam/Michael agreed. "We realised we could cause so much more destruction if we teamed up!"

Castiel turned, and there was Gabriel grinning at him.

"All my idea," he boasted, holding his hand up for a high-five. Castiel started towards him, but flames sprang up – just ordinary fire, but it could burn him now, and he couldn't hold it back but cried out –

"Cas! Cas, wake up!"

Castiel sat bolt upright, his eyes snapping open. Dean, who had been shaking him, jumped back.

"Hey, take it easy, it was just a dream," he said.

"A nightmare." Castiel felt shaken. "Is that what they're like?"

Cas still wasn't an expert on human expressions, but Dean looked shocked.

"You've never had one?"

"Angels do not sleep. I knew what they were, but I had no idea they could be so…"

"…terrifying?" Dean finished for him. "Yeah."

The two of them sat in silence for a minute. Castiel was struggling with the jumble of images in his mind, nothing like the clarity and objectivity he was used to.

"Dean," he said after a moment.

"Cas."

"Is it really like this for you and Sam… constantly?"

Dean raised his eyebrows, then shrugged.

"Pretty much. Though we're better-looking than you."

On that note, he stood.

"Try to get back to sleep. You'll need it in the morning."

When Dean left, Castiel found himself staring at the door and contemplating some of the more unmentionable demands of his newly insistent body. Maybe some of them weren't as terrible as he'd though. He sat for some time, reluctant to risk another nightmare; but eventually, as it tended to now, his body overcame him again.